diff --git a/.github/workflows/stage-4-acceptance.yaml b/.github/workflows/stage-4-acceptance.yaml
index d239f70c..806a2afa 100644
--- a/.github/workflows/stage-4-acceptance.yaml
+++ b/.github/workflows/stage-4-acceptance.yaml
@@ -87,6 +87,7 @@ jobs:
         uses: actions/checkout@v5
       - name: "Run UI test"
         run: |
+          cp .env.example .env
           make test-ui
       - name: "Save result"
         run: |
diff --git a/.gitignore b/.gitignore
index d5e07a30..37b09f0a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,3 +19,4 @@ lung_cancer_screening/assets/compiled/*
 .DS_Store
 .venv
 .devcontainer/ca.crt
+tests/TEST-*.xml
diff --git a/lung_cancer_screening/core/tests/acceptance/test_cannot_change_answers_after_submission.py b/lung_cancer_screening/core/tests/acceptance/test_cannot_change_answers_after_submission.py
deleted file mode 100644
index 5f00b621..00000000
--- a/lung_cancer_screening/core/tests/acceptance/test_cannot_change_answers_after_submission.py
+++ /dev/null
@@ -1,64 +0,0 @@
-import os
-from django.contrib.staticfiles.testing import StaticLiveServerTestCase
-from playwright.sync_api import sync_playwright, expect
-from datetime import datetime
-from dateutil.relativedelta import relativedelta
-
-from .helpers.user_interaction_helpers import (
-    fill_in_and_submit_height_metric,
-    fill_in_and_submit_weight_metric,
-    fill_in_and_submit_participant_id,
-    fill_in_and_submit_smoking_eligibility,
-    fill_in_and_submit_date_of_birth,
-    fill_in_and_submit_sex_at_birth,
-    fill_in_and_submit_gender,
-    fill_in_and_submit_ethnicity,
-    fill_in_and_submit_asbestos_exposure,
-    fill_in_and_submit_respiratory_conditions
-)
-
-class TestQuestionnaire(StaticLiveServerTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
-        super().setUpClass()
-        cls.playwright = sync_playwright().start()
-        cls.browser = cls.playwright.chromium.launch()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls.browser.close()
-        cls.playwright.stop()
-
-    def test_cannot_change_responses_once_checked_and_submitted(self):
-        participant_id = '123'
-        smoking_status = 'Yes, I used to smoke regularly'
-        age = datetime.now() - relativedelta(years=55)
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-        fill_in_and_submit_smoking_eligibility(page, smoking_status)
-        fill_in_and_submit_date_of_birth(page, age)
-        fill_in_and_submit_height_metric(page, "170")
-        fill_in_and_submit_weight_metric(page, "25.4")
-        fill_in_and_submit_sex_at_birth(page, "Male")
-        fill_in_and_submit_gender(page, "Male")
-        fill_in_and_submit_ethnicity(page, "White")
-        page.click("text=Continue") # education
-        fill_in_and_submit_respiratory_conditions(page, "No, I have not had any of these respiratory conditions")
-        fill_in_and_submit_asbestos_exposure(page, "No")
-        page.click("text=Continue") # cancer diagnosis
-        page.click("text=Continue") # family history
-        page.click("text=Submit")
-
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-
-        expect(page.locator('#maincontent')).to_contain_text(
-            "Responses have already been submitted for this participant"
-        )
diff --git a/lung_cancer_screening/core/tests/acceptance/test_participant_not_smoker.py b/lung_cancer_screening/core/tests/acceptance/test_participant_not_smoker.py
deleted file mode 100644
index a352d49e..00000000
--- a/lung_cancer_screening/core/tests/acceptance/test_participant_not_smoker.py
+++ /dev/null
@@ -1,39 +0,0 @@
-import os
-from django.contrib.staticfiles.testing import StaticLiveServerTestCase
-from playwright.sync_api import sync_playwright, expect
-
-
-from .helpers.user_interaction_helpers import (
-    fill_in_and_submit_participant_id,
-    fill_in_and_submit_smoking_eligibility
-)
-
-
-class TestParticipantNotSmoker(StaticLiveServerTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
-        super().setUpClass()
-        cls.playwright = sync_playwright().start()
-        cls.browser = cls.playwright.chromium.launch()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls.browser.close()
-        cls.playwright.stop()
-
-    def test_participant_not_smoker(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-        fill_in_and_submit_smoking_eligibility(page, 'No, I have never smoked')
-
-        expect(page).to_have_url(f"{self.live_server_url}/non-smoker-exit")
-
-        expect(page.locator(".title")).to_have_text(
-            "You do not need an NHS lung health check")
diff --git a/lung_cancer_screening/core/tests/acceptance/test_participant_out_of_age_range.py b/lung_cancer_screening/core/tests/acceptance/test_participant_out_of_age_range.py
deleted file mode 100644
index e146d60f..00000000
--- a/lung_cancer_screening/core/tests/acceptance/test_participant_out_of_age_range.py
+++ /dev/null
@@ -1,44 +0,0 @@
-import os
-from django.contrib.staticfiles.testing import StaticLiveServerTestCase
-from playwright.sync_api import sync_playwright, expect
-from datetime import datetime
-from dateutil.relativedelta import relativedelta
-
-from .helpers.user_interaction_helpers import (
-    fill_in_and_submit_participant_id,
-    fill_in_and_submit_smoking_eligibility,
-    fill_in_and_submit_date_of_birth
-)
-
-
-class TestParticipantOutOfAgeRange(StaticLiveServerTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
-        super().setUpClass()
-        cls.playwright = sync_playwright().start()
-        cls.browser = cls.playwright.chromium.launch()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls.browser.close()
-        cls.playwright.stop()
-
-    def test_participant_out_of_age_range(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-        fill_in_and_submit_smoking_eligibility(page, 'Yes, I used to smoke regularly')
-
-        age = datetime.now() - relativedelta(years=20)
-        fill_in_and_submit_date_of_birth(page, age)
-
-        expect(page).to_have_url(f"{self.live_server_url}/age-range-exit")
-
-        expect(page.locator(".title")).to_have_text(
-            "You do not need an NHS lung health check")
diff --git a/lung_cancer_screening/core/tests/acceptance/test_questionnaire.py b/lung_cancer_screening/core/tests/acceptance/test_questionnaire.py
deleted file mode 100644
index f6bbbaf4..00000000
--- a/lung_cancer_screening/core/tests/acceptance/test_questionnaire.py
+++ /dev/null
@@ -1,162 +0,0 @@
-import os
-from django.contrib.staticfiles.testing import StaticLiveServerTestCase
-from playwright.sync_api import sync_playwright, expect
-from datetime import datetime
-from dateutil.relativedelta import relativedelta
-
-from .helpers.user_interaction_helpers import (
-    fill_in_and_submit_height_imperial,
-    fill_in_and_submit_height_metric,
-    fill_in_and_submit_participant_id,
-    fill_in_and_submit_smoking_eligibility,
-    fill_in_and_submit_date_of_birth,
-    fill_in_and_submit_weight_metric,
-    fill_in_and_submit_weight_imperial,
-    fill_in_and_submit_sex_at_birth,
-    fill_in_and_submit_gender,
-    fill_in_and_submit_ethnicity,
-    fill_in_and_submit_asbestos_exposure,
-    fill_in_and_submit_respiratory_conditions
-)
-
-from .helpers.assertion_helpers import expect_back_link_to_have_url
-
-class TestQuestionnaire(StaticLiveServerTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
-        super().setUpClass()
-        cls.playwright = sync_playwright().start()
-        cls.browser = cls.playwright.chromium.launch()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls.browser.close()
-        cls.playwright.stop()
-
-    def test_full_questionnaire_user_journey(self):
-        participant_id = '123'
-        smoking_status = 'Yes, I used to smoke regularly'
-        age = datetime.now() - relativedelta(years=55)
-        height = "170"
-        feet = 5
-        inches = 7
-        weight_metric = 70
-        weight_stone = 5
-        weight_pound = 10
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-
-        expect(page).to_have_url(
-            f"{self.live_server_url}/have-you-ever-smoked")
-        expect_back_link_to_have_url(page, "/start")
-        fill_in_and_submit_smoking_eligibility(page, smoking_status)
-
-        expect(page).to_have_url(f"{self.live_server_url}/date-of-birth")
-        expect_back_link_to_have_url(page, "/have-you-ever-smoked")
-        fill_in_and_submit_date_of_birth(page, age)
-
-        expect(page).to_have_url(f"{self.live_server_url}/height")
-        expect_back_link_to_have_url(page, "/date-of-birth")
-        fill_in_and_submit_height_metric(page, height)
-
-        page.click("text=Back")
-        expect(page).to_have_url(f"{self.live_server_url}/height")
-        page.click("text=Switch to imperial")
-        fill_in_and_submit_height_imperial(page, feet, inches)
-
-        expect(page).to_have_url(f"{self.live_server_url}/weight")
-        expect_back_link_to_have_url(page, "/height")
-        fill_in_and_submit_weight_metric(page, weight_metric)
-        page.click("text=Back")
-
-        expect(page).to_have_url(f"{self.live_server_url}/weight")
-        page.get_by_role("link", name="Switch to stone and pounds").click()
-        fill_in_and_submit_weight_imperial(page, weight_stone, weight_pound)
-
-        expect(page).to_have_url(f"{self.live_server_url}/sex-at-birth")
-        expect_back_link_to_have_url(page, "/weight")
-        fill_in_and_submit_sex_at_birth(page, "Male")
-
-        expect(page).to_have_url(f"{self.live_server_url}/gender")
-        expect_back_link_to_have_url(page, "/sex-at-birth")
-        fill_in_and_submit_gender(page, "Male")
-
-        expect(page).to_have_url(f"{self.live_server_url}/ethnicity")
-        expect_back_link_to_have_url(page, "/gender")
-        fill_in_and_submit_ethnicity(page, "White")
-
-        expect(page).to_have_url(f"{self.live_server_url}/education")
-        expect_back_link_to_have_url(page, "/ethnicity")
-        page.click("text=Continue")
-
-        expect(page).to_have_url(f"{self.live_server_url}/respiratory-conditions")
-        expect_back_link_to_have_url(page, "/education")
-        fill_in_and_submit_respiratory_conditions(page, "No, I have not had any of these respiratory conditions")
-
-        expect(page).to_have_url(f"{self.live_server_url}/asbestos-exposure")
-        expect_back_link_to_have_url(page, "/respiratory-conditions")
-        fill_in_and_submit_asbestos_exposure(page, "No")
-
-        expect(page).to_have_url(f"{self.live_server_url}/cancer-diagnosis")
-        expect_back_link_to_have_url(page, "/asbestos-exposure")
-        page.click("text=Continue")
-
-        expect(page).to_have_url(f"{self.live_server_url}/family-history-lung-cancer")
-        expect_back_link_to_have_url(page, "/cancer-diagnosis")
-        page.click("text=Continue")
-
-        expect(page).to_have_url(f"{self.live_server_url}/responses")
-        expect_back_link_to_have_url(page, "/family-history-lung-cancer")
-
-        responses = page.locator(".responses")
-        expect(responses).to_contain_text("Have you ever smoked? Yes, I used to smoke regularly")
-        expect(responses).to_contain_text(age.strftime("What is your date of birth? %Y-%m-%d"))
-        expect(responses).to_contain_text(f"What is your height? {feet} feet {inches} inches")
-        expect(responses).to_contain_text(f"What is your weight? {weight_stone} stone {weight_pound} pound")
-        expect(responses).to_contain_text("What was your sex at birth? Male")
-        expect(responses).to_contain_text("Which of these best describes you? Male")
-        expect(responses).to_contain_text("What is your ethnic background? White")
-        expect(responses).to_contain_text("Have you ever worked in a job where you might have been exposed to asbestos? No")
-        expect(responses).to_contain_text("Have you ever been diagnosed with any of the following respiratory conditions? No, I have not had any of these respiratory conditions")
-
-        page.click("text=Submit")
-
-        expect(page).to_have_url(f"{self.live_server_url}/your-results")
-
-    def test_can_select_multiple_respiratory_conditions(self):
-        """Test that users can select multiple respiratory conditions in the UI"""
-        participant_id = '456'
-        smoking_status = 'Yes, I currently smoke'
-        age = datetime.now() - relativedelta(years=60)
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-
-        fill_in_and_submit_participant_id(page, participant_id)
-        fill_in_and_submit_smoking_eligibility(page, smoking_status)
-        fill_in_and_submit_date_of_birth(page, age)
-        fill_in_and_submit_height_metric(page, "170")
-        fill_in_and_submit_weight_metric(page, "70")
-        fill_in_and_submit_sex_at_birth(page, "Female")
-        fill_in_and_submit_gender(page, "Female")
-        fill_in_and_submit_ethnicity(page, "White")
-        page.click("text=Continue")  # education
-
-        # Select multiple respiratory conditions
-        expect(page).to_have_url(f"{self.live_server_url}/respiratory-conditions")
-        fill_in_and_submit_respiratory_conditions(page, ["Pneumonia", "Emphysema"])
-
-        fill_in_and_submit_asbestos_exposure(page, "No")
-        page.click("text=Continue")  # cancer diagnosis
-        page.click("text=Continue")  # family history
-
-        # Verify both conditions appear on the responses page
-        expect(page).to_have_url(f"{self.live_server_url}/responses")
-        responses = page.locator(".responses")
-        expect(responses).to_contain_text("Have you ever been diagnosed with any of the following respiratory conditions? Pneumonia, Emphysema")
diff --git a/lung_cancer_screening/core/tests/acceptance/test_questionnaire_validation_errors.py b/lung_cancer_screening/core/tests/acceptance/test_questionnaire_validation_errors.py
deleted file mode 100644
index efc35f90..00000000
--- a/lung_cancer_screening/core/tests/acceptance/test_questionnaire_validation_errors.py
+++ /dev/null
@@ -1,151 +0,0 @@
-import os
-from django.contrib.staticfiles.testing import StaticLiveServerTestCase
-from playwright.sync_api import sync_playwright, expect
-
-from .helpers.user_interaction_helpers import (
-    fill_in_and_submit_participant_id
-)
-
-class TestQuestionnaireValidationErrors(StaticLiveServerTestCase):
-
-    @classmethod
-    def setUpClass(cls):
-        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
-        super().setUpClass()
-        cls.playwright = sync_playwright().start()
-        cls.browser = cls.playwright.chromium.launch()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls.browser.close()
-        cls.playwright.stop()
-
-    def test_date_of_birth_validation_errors(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-        fill_in_and_submit_participant_id(page, participant_id)
-        page.goto(f"{self.live_server_url}/date-of-birth")
-
-        expect(page.locator("legend")).to_have_text(
-            "What is your date of birth?")
-
-        page.click("text=Continue")
-
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Enter your date of birth."
-        )
-
-    def test_height_validation_errors(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-        fill_in_and_submit_participant_id(page, participant_id)
-        page.goto(f"{self.live_server_url}/height")
-
-        page.click("text=Continue")
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Enter your height."
-        )
-
-        page.get_by_label("Centimetre").fill('139.6')
-        page.click('text=Continue')
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Height must be between 139.7cm and 243.8 cm"
-        )
-
-        page.get_by_label("Centimetre").fill('243.9')
-        page.click('text=Continue')
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Height must be between 139.7cm and 243.8 cm"
-        )
-
-        page.click("text=Switch to imperial")
-
-        page.click("text=Continue")
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Enter your height."
-        )
-
-        page.get_by_label("Feet").fill('5.2')
-        page.get_by_label("Inches").fill('2')
-        page.click('text=Continue')
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Feet must be in whole numbers"
-        )
-
-        page.get_by_label("Feet").fill('5')
-        page.get_by_label("Inches").fill('2.2')
-        page.click('text=Continue')
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Inches must be in whole numbers"
-        )
-
-    def test_weight_validation_errors(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-        fill_in_and_submit_participant_id(page, participant_id)
-        page.goto(f"{self.live_server_url}/weight")
-
-        page.click("text=Continue")
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Enter your weight."
-        )
-        # Test weight below minimum
-        page.get_by_label("Kilograms").fill('25.3')
-        page.click('text=Continue')
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Weight must be between 25.4kg and 317.5kg"
-        )
-
-    def test_ethnicity_validation_errors(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-        fill_in_and_submit_participant_id(page, participant_id)
-        page.goto(f"{self.live_server_url}/ethnicity")
-
-        page.click("text=Continue")
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Select your ethnic background."
-        )
-
-    def test_respiratory_conditions_validation_errors(self):
-        participant_id = '123'
-
-        page = self.browser.new_page()
-        page.goto(f"{self.live_server_url}/start")
-        fill_in_and_submit_participant_id(page, participant_id)
-        page.goto(f"{self.live_server_url}/respiratory-conditions")
-
-        page.click("text=Continue")
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Select if you have had any respiratory conditions"
-        )
-
-        # Select one respiratory condition
-        page.get_by_label("Bronchitis").click()
-
-        # Select None option
-        page.get_by_label("No, I have not had any of these respiratory conditions").click()
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Select if you have had any respiratory conditions"
-        )
-
-        # Continue
-        page.click("text=Continue")
-
-        # Assert error is shown
-        expect(page.locator(".nhsuk-error-message")).to_contain_text(
-            "Select if you have had any respiratory conditions, or select 'No, I have not had any of these respiratory conditions'"
-        )
-
-        expect(page).to_have_url(f"{self.live_server_url}/respiratory-conditions")
-
-
diff --git a/lung_cancer_screening/settings_test.py b/lung_cancer_screening/settings_test.py
index ae9441b3..b7a69ab0 100644
--- a/lung_cancer_screening/settings_test.py
+++ b/lung_cancer_screening/settings_test.py
@@ -13,4 +13,6 @@
     "whitenoise.middleware.WhiteNoiseMiddleware",
 )
 
+INSTALLED_APPS += ["behave_django"]
+
 logging.disable(logging.CRITICAL)
diff --git a/poetry.lock b/poetry.lock
index 1a4b5a5d..6ce8e73b 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -6,7 +6,7 @@ version = "3.10.0"
 description = "ASGI specs, helper code, and adapters"
 optional = false
 python-versions = ">=3.9"
-groups = ["main"]
+groups = ["main", "dev"]
 files = [
     {file = "asgiref-3.10.0-py3-none-any.whl", hash = "sha256:aef8a81283a34d0ab31630c9b7dfe70c812c95eba78171367ca8745e88124734"},
     {file = "asgiref-3.10.0.tar.gz", hash = "sha256:d89f2d8cd8b56dada7d52fa7dc8075baa08fb836560710d38c292a7a3f78c04e"},
@@ -72,6 +72,72 @@ msal = ">=1.30.0"
 msal-extensions = ">=1.2.0"
 typing-extensions = ">=4.0.0"
 
+[[package]]
+name = "beautifulsoup4"
+version = "4.14.2"
+description = "Screen-scraping library"
+optional = false
+python-versions = ">=3.7.0"
+groups = ["dev"]
+files = [
+    {file = "beautifulsoup4-4.14.2-py3-none-any.whl", hash = "sha256:5ef6fa3a8cbece8488d66985560f97ed091e22bbc4e9c2338508a9d5de6d4515"},
+    {file = "beautifulsoup4-4.14.2.tar.gz", hash = "sha256:2a98ab9f944a11acee9cc848508ec28d9228abfd522ef0fad6a02a72e0ded69e"},
+]
+
+[package.dependencies]
+soupsieve = ">1.2"
+typing-extensions = ">=4.0.0"
+
+[package.extras]
+cchardet = ["cchardet"]
+chardet = ["chardet"]
+charset-normalizer = ["charset-normalizer"]
+html5lib = ["html5lib"]
+lxml = ["lxml"]
+
+[[package]]
+name = "behave"
+version = "1.3.3"
+description = "behave is behaviour-driven development, Python style"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,>=2.7"
+groups = ["dev"]
+files = [
+    {file = "behave-1.3.3-py2.py3-none-any.whl", hash = "sha256:89bdb62af8fb9f147ce245736a5de69f025e5edfb66f1fbe16c5007493f842c0"},
+    {file = "behave-1.3.3.tar.gz", hash = "sha256:2b8f4b64ed2ea756a5a2a73e23defc1c4631e9e724c499e46661778453ebaf51"},
+]
+
+[package.dependencies]
+colorama = ">=0.3.7"
+cucumber-expressions = {version = ">=17.1.0", markers = "python_version >= \"3.8\""}
+cucumber-tag-expressions = ">=4.1.0"
+parse = ">=1.18.0"
+parse-type = ">=0.6.0"
+six = ">=1.15.0"
+
+[package.extras]
+develop = ["PyHamcrest (<2.0) ; python_version < \"3.0\"", "PyHamcrest (>=2.0.2) ; python_version >= \"3.0\"", "build (>=0.5.1)", "coverage (>=5.0)", "invoke (>=1.7.0) ; python_version >= \"3.6\"", "invoke (>=1.7.0,<2.0) ; python_version < \"3.6\"", "mock (<4.0) ; python_version < \"3.6\"", "mock (>=4.0) ; python_version >= \"3.6\"", "modernize (>=0.5)", "path (>=13.1.0) ; python_version >= \"3.5\"", "path.py (>=11.5.0) ; python_version < \"3.5\"", "pycmd", "pylint", "pytest (>=4.2,<5.0) ; python_version < \"3.0\"", "pytest (>=5.0) ; python_version >= \"3.0\"", "pytest-cov", "pytest-html (>=1.19.0,<2.0) ; python_version < \"3.0\"", "pytest-html (>=2.0) ; python_version >= \"3.0\"", "ruff ; python_version >= \"3.7\"", "tox (>=3.28.0,<4.0)", "twine (>=1.13.0)", "virtualenv (<20.22.0) ; python_version < \"3.7\"", "virtualenv (>=20.26.6) ; python_version >= \"3.7\""]
+docs = ["furo (>=2024.04.27) ; python_version >= \"3.8\"", "sphinx (>=1.6,<4.4) ; python_version < \"3.7\"", "sphinx (>=7.4.0) ; python_version >= \"3.7\"", "sphinx-copybutton (>=0.5.2) ; python_version >= \"3.7\"", "sphinxcontrib-applehelp (>=1.0.8) ; python_version >= \"3.7\"", "sphinxcontrib-htmlhelp (>=2.0.5) ; python_version >= \"3.7\""]
+formatters = ["behave-html-formatter (>=0.9.10) ; python_version >= \"3.6\"", "behave-html-pretty-formatter (>=1.9.1) ; python_version >= \"3.6\""]
+testing = ["PyHamcrest (<2.0) ; python_version < \"3.0\"", "PyHamcrest (>=2.0.2) ; python_version >= \"3.0\"", "assertpy (>=1.1)", "chardet", "freezegun (>=1.5.1) ; python_version > \"3.7\"", "mock (<4.0) ; python_version < \"3.6\"", "mock (>=4.0) ; python_version >= \"3.6\"", "path (>=13.1.0) ; python_version >= \"3.5\"", "path.py (>=11.5.0,<13.0) ; python_version < \"3.5\"", "pytest (<5.0) ; python_version < \"3.0\"", "pytest (>=5.0) ; python_version >= \"3.0\"", "pytest-html (>=1.19.0,<2.0) ; python_version < \"3.0\"", "pytest-html (>=2.0) ; python_version >= \"3.0\""]
+
+[[package]]
+name = "behave-django"
+version = "1.9.0"
+description = "Behave BDD integration for Django"
+optional = false
+python-versions = ">=3.9"
+groups = ["dev"]
+files = [
+    {file = "behave_django-1.9.0-py3-none-any.whl", hash = "sha256:41c6d95886cd59413493037cc79fbe3346a828c83594431bbd596859ad12399b"},
+    {file = "behave_django-1.9.0.tar.gz", hash = "sha256:cbae403b9c9873d4d079f3560d6c8b390eaea9fb8e8caff63439a0b06ea60309"},
+]
+
+[package.dependencies]
+beautifulsoup4 = "*"
+behave = ">=1.3.3"
+django = ">=4.2"
+
 [[package]]
 name = "certifi"
 version = "2025.11.12"
@@ -305,6 +371,18 @@ files = [
     {file = "charset_normalizer-3.4.4.tar.gz", hash = "sha256:94537985111c35f28720e43603b8e7b43a6ecfb2ce1d3058bbe955b73404e21a"},
 ]
 
+[[package]]
+name = "colorama"
+version = "0.4.6"
+description = "Cross-platform colored terminal text."
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,!=3.5.*,!=3.6.*,>=2.7"
+groups = ["dev"]
+files = [
+    {file = "colorama-0.4.6-py2.py3-none-any.whl", hash = "sha256:4f1d9991f5acc0ca119f9d443620b77f9d6b33703e51011c16baf57afb285fc6"},
+    {file = "colorama-0.4.6.tar.gz", hash = "sha256:08695f5cb7ed6e0531a20572697297273c47b8cae5a63ffc6d6ed5c201be6e44"},
+]
+
 [[package]]
 name = "cryptography"
 version = "46.0.3"
@@ -382,13 +460,37 @@ ssh = ["bcrypt (>=3.1.5)"]
 test = ["certifi (>=2024)", "cryptography-vectors (==46.0.3)", "pretend (>=0.7)", "pytest (>=7.4.0)", "pytest-benchmark (>=4.0)", "pytest-cov (>=2.10.1)", "pytest-xdist (>=3.5.0)"]
 test-randomorder = ["pytest-randomly"]
 
+[[package]]
+name = "cucumber-expressions"
+version = "18.0.1"
+description = "Cucumber Expressions - a simpler alternative to Regular Expressions"
+optional = false
+python-versions = "<4.0,>=3.8"
+groups = ["dev"]
+files = [
+    {file = "cucumber_expressions-18.0.1-py3-none-any.whl", hash = "sha256:86230d503cdda7ef35a1f2072a882d7d57c740aa4c163c82b07f039b6bc60c42"},
+    {file = "cucumber_expressions-18.0.1.tar.gz", hash = "sha256:86ce41bf28ee520408416f38022e5a083d815edf04a0bd1dae46d474ca597c60"},
+]
+
+[[package]]
+name = "cucumber-tag-expressions"
+version = "8.0.0"
+description = "Provides a tag-expression parser and evaluation logic for cucumber/behave"
+optional = false
+python-versions = ">=3.10"
+groups = ["dev"]
+files = [
+    {file = "cucumber_tag_expressions-8.0.0-py3-none-any.whl", hash = "sha256:bfe552226f62a4462ee91c9643582f524af84ac84952643fb09057580cbb110a"},
+    {file = "cucumber_tag_expressions-8.0.0.tar.gz", hash = "sha256:4af80282ff0349918c332428176089094019af6e2a381a2fd8f1c62a7a6bb7e8"},
+]
+
 [[package]]
 name = "django"
 version = "5.2.8"
 description = "A high-level Python web framework that encourages rapid development and clean, pragmatic design."
 optional = false
 python-versions = ">=3.10"
-groups = ["main"]
+groups = ["main", "dev"]
 files = [
     {file = "django-5.2.8-py3-none-any.whl", hash = "sha256:37e687f7bd73ddf043e2b6b97cfe02fcbb11f2dbb3adccc6a2b18c6daa054d7f"},
     {file = "django-5.2.8.tar.gz", hash = "sha256:23254866a5bb9a2cfa6004e8b809ec6246eba4b58a7589bc2772f1bcc8456c7f"},
@@ -419,8 +521,6 @@ files = [
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     {file = "greenlet-3.2.4-cp310-cp310-musllinux_1_1_aarch64.whl", hash = "sha256:9fe0a28a7b952a21e2c062cd5756d34354117796c6d9215a87f55e38d15402c5"},
     {file = "greenlet-3.2.4-cp310-cp310-musllinux_1_1_x86_64.whl", hash = "sha256:8854167e06950ca75b898b104b63cc646573aa5fef1353d4508ecdd1ee76254f"},
-    {file = "greenlet-3.2.4-cp310-cp310-musllinux_1_2_aarch64.whl", hash = "sha256:f47617f698838ba98f4ff4189aef02e7343952df3a615f847bb575c3feb177a7"},
-    {file = "greenlet-3.2.4-cp310-cp310-musllinux_1_2_x86_64.whl", hash = "sha256:af41be48a4f60429d5cad9d22175217805098a9ef7c40bfef44f7669fb9d74d8"},
     {file = "greenlet-3.2.4-cp310-cp310-win_amd64.whl", hash = "sha256:73f49b5368b5359d04e18d15828eecc1806033db5233397748f4ca813ff1056c"},
     {file = "greenlet-3.2.4-cp311-cp311-macosx_11_0_universal2.whl", hash = "sha256:96378df1de302bc38e99c3a9aa311967b7dc80ced1dcc6f171e99842987882a2"},
     {file = "greenlet-3.2.4-cp311-cp311-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:1ee8fae0519a337f2329cb78bd7a8e128ec0f881073d43f023c7b8d4831d5246"},
@@ -430,8 +530,6 @@ files = [
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-    {file = "greenlet-3.2.4-cp311-cp311-musllinux_1_2_aarch64.whl", hash = "sha256:c9c6de1940a7d828635fbd254d69db79e54619f165ee7ce32fda763a9cb6a58c"},
-    {file = "greenlet-3.2.4-cp311-cp311-musllinux_1_2_x86_64.whl", hash = "sha256:03c5136e7be905045160b1b9fdca93dd6727b180feeafda6818e6496434ed8c5"},
     {file = "greenlet-3.2.4-cp311-cp311-win_amd64.whl", hash = "sha256:9c40adce87eaa9ddb593ccb0fa6a07caf34015a29bf8d344811665b573138db9"},
     {file = "greenlet-3.2.4-cp312-cp312-macosx_11_0_universal2.whl", hash = "sha256:3b67ca49f54cede0186854a008109d6ee71f66bd57bb36abd6d0a0267b540cdd"},
     {file = "greenlet-3.2.4-cp312-cp312-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:ddf9164e7a5b08e9d22511526865780a576f19ddd00d62f8a665949327fde8bb"},
@@ -441,8 +539,6 @@ files = [
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     {file = "greenlet-3.2.4-cp312-cp312-musllinux_1_1_aarch64.whl", hash = "sha256:abbf57b5a870d30c4675928c37278493044d7c14378350b3aa5d484fa65575f0"},
     {file = "greenlet-3.2.4-cp312-cp312-musllinux_1_1_x86_64.whl", hash = "sha256:20fb936b4652b6e307b8f347665e2c615540d4b42b3b4c8a321d8286da7e520f"},
-    {file = "greenlet-3.2.4-cp312-cp312-musllinux_1_2_aarch64.whl", hash = "sha256:ee7a6ec486883397d70eec05059353b8e83eca9168b9f3f9a361971e77e0bcd0"},
-    {file = "greenlet-3.2.4-cp312-cp312-musllinux_1_2_x86_64.whl", hash = "sha256:326d234cbf337c9c3def0676412eb7040a35a768efc92504b947b3e9cfc7543d"},
     {file = "greenlet-3.2.4-cp312-cp312-win_amd64.whl", hash = "sha256:a7d4e128405eea3814a12cc2605e0e6aedb4035bf32697f72deca74de4105e02"},
     {file = "greenlet-3.2.4-cp313-cp313-macosx_11_0_universal2.whl", hash = "sha256:1a921e542453fe531144e91e1feedf12e07351b1cf6c9e8a3325ea600a715a31"},
     {file = "greenlet-3.2.4-cp313-cp313-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:cd3c8e693bff0fff6ba55f140bf390fa92c994083f838fece0f63be121334945"},
@@ -452,8 +548,6 @@ files = [
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     {file = "greenlet-3.2.4-cp313-cp313-musllinux_1_1_aarch64.whl", hash = "sha256:00fadb3fedccc447f517ee0d3fd8fe49eae949e1cd0f6a611818f4f6fb7dc83b"},
     {file = "greenlet-3.2.4-cp313-cp313-musllinux_1_1_x86_64.whl", hash = "sha256:d25c5091190f2dc0eaa3f950252122edbbadbb682aa7b1ef2f8af0f8c0afefae"},
-    {file = "greenlet-3.2.4-cp313-cp313-musllinux_1_2_aarch64.whl", hash = "sha256:6e343822feb58ac4d0a1211bd9399de2b3a04963ddeec21530fc426cc121f19b"},
-    {file = "greenlet-3.2.4-cp313-cp313-musllinux_1_2_x86_64.whl", hash = "sha256:ca7f6f1f2649b89ce02f6f229d7c19f680a6238af656f61e0115b24857917929"},
     {file = "greenlet-3.2.4-cp313-cp313-win_amd64.whl", hash = "sha256:554b03b6e73aaabec3745364d6239e9e012d64c68ccd0b8430c64ccc14939a8b"},
     {file = "greenlet-3.2.4-cp314-cp314-macosx_11_0_universal2.whl", hash = "sha256:49a30d5fda2507ae77be16479bdb62a660fa51b1eb4928b524975b3bde77b3c0"},
     {file = "greenlet-3.2.4-cp314-cp314-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:299fd615cd8fc86267b47597123e3f43ad79c9d8a22bebdce535e53550763e2f"},
@@ -461,8 +555,6 @@ files = [
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     {file = "greenlet-3.2.4-cp314-cp314-manylinux2014_x86_64.manylinux_2_17_x86_64.whl", hash = "sha256:061dc4cf2c34852b052a8620d40f36324554bc192be474b9e9770e8c042fd735"},
     {file = "greenlet-3.2.4-cp314-cp314-manylinux_2_24_x86_64.manylinux_2_28_x86_64.whl", hash = "sha256:44358b9bf66c8576a9f57a590d5f5d6e72fa4228b763d0e43fee6d3b06d3a337"},
-    {file = "greenlet-3.2.4-cp314-cp314-musllinux_1_2_aarch64.whl", hash = "sha256:2917bdf657f5859fbf3386b12d68ede4cf1f04c90c3a6bc1f013dd68a22e2269"},
-    {file = "greenlet-3.2.4-cp314-cp314-musllinux_1_2_x86_64.whl", hash = "sha256:015d48959d4add5d6c9f6c5210ee3803a830dce46356e3bc326d6776bde54681"},
     {file = "greenlet-3.2.4-cp314-cp314-win_amd64.whl", hash = "sha256:e37ab26028f12dbb0ff65f29a8d3d44a765c61e729647bf2ddfbbed621726f01"},
     {file = "greenlet-3.2.4-cp39-cp39-macosx_11_0_universal2.whl", hash = "sha256:b6a7c19cf0d2742d0809a4c05975db036fdff50cd294a93632d6a310bf9ac02c"},
     {file = "greenlet-3.2.4-cp39-cp39-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:27890167f55d2387576d1f41d9487ef171849ea0359ce1510ca6e06c8bece11d"},
@@ -472,8 +564,6 @@ files = [
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     {file = "greenlet-3.2.4-cp39-cp39-musllinux_1_1_x86_64.whl", hash = "sha256:81701fd84f26330f0d5f4944d4e92e61afe6319dcd9775e39396e39d7c3e5f98"},
-    {file = "greenlet-3.2.4-cp39-cp39-musllinux_1_2_aarch64.whl", hash = "sha256:28a3c6b7cd72a96f61b0e4b2a36f681025b60ae4779cc73c1535eb5f29560b10"},
-    {file = "greenlet-3.2.4-cp39-cp39-musllinux_1_2_x86_64.whl", hash = "sha256:52206cd642670b0b320a1fd1cbfd95bca0e043179c1d8a045f2c6109dfe973be"},
     {file = "greenlet-3.2.4-cp39-cp39-win32.whl", hash = "sha256:65458b409c1ed459ea899e939f0e1cdb14f58dbc803f2f93c5eab5694d32671b"},
     {file = "greenlet-3.2.4-cp39-cp39-win_amd64.whl", hash = "sha256:d2e685ade4dafd447ede19c31277a224a239a0a1a4eca4e6390efedf20260cfb"},
     {file = "greenlet-3.2.4.tar.gz", hash = "sha256:0dca0d95ff849f9a364385f36ab49f50065d76964944638be9691e1832e9f86d"},
@@ -702,6 +792,39 @@ files = [
     {file = "packaging-25.0.tar.gz", hash = "sha256:d443872c98d677bf60f6a1f2f8c1cb748e8fe762d2bf9d3148b5599295b0fc4f"},
 ]
 
+[[package]]
+name = "parse"
+version = "1.20.2"
+description = "parse() is the opposite of format()"
+optional = false
+python-versions = "*"
+groups = ["dev"]
+files = [
+    {file = "parse-1.20.2-py2.py3-none-any.whl", hash = "sha256:967095588cb802add9177d0c0b6133b5ba33b1ea9007ca800e526f42a85af558"},
+    {file = "parse-1.20.2.tar.gz", hash = "sha256:b41d604d16503c79d81af5165155c0b20f6c8d6c559efa66b4b695c3e5a0a0ce"},
+]
+
+[[package]]
+name = "parse-type"
+version = "0.6.6"
+description = "Simplifies to build parse types based on the parse module"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,>=2.7"
+groups = ["dev"]
+files = [
+    {file = "parse_type-0.6.6-py2.py3-none-any.whl", hash = "sha256:3ca79bbe71e170dfccc8ec6c341edfd1c2a0fc1e5cfd18330f93af938de2348c"},
+    {file = "parse_type-0.6.6.tar.gz", hash = "sha256:513a3784104839770d690e04339a8b4d33439fcd5dd99f2e4580f9fc1097bfb2"},
+]
+
+[package.dependencies]
+parse = {version = ">=1.18.0", markers = "python_version >= \"3.0\""}
+six = ">=1.15"
+
+[package.extras]
+develop = ["build (>=0.5.1)", "coverage (>=4.4)", "pylint", "pytest (<5.0) ; python_version < \"3.0\"", "pytest (>=5.0) ; python_version >= \"3.0\"", "pytest-cov", "pytest-html (>=1.19.0)", "ruff ; python_version >= \"3.7\"", "setuptools", "setuptools-scm", "tox (>=2.8,<4.0)", "twine (>=1.13.0)", "virtualenv (<20.22.0) ; python_version <= \"3.6\"", "virtualenv (>=20.0.0) ; python_version > \"3.6\"", "wheel"]
+docs = ["Sphinx (>=1.6)", "sphinx_bootstrap_theme (>=0.6.0)"]
+testing = ["pytest (<5.0) ; python_version < \"3.0\"", "pytest (>=5.0) ; python_version >= \"3.0\"", "pytest-html (>=1.19.0)"]
+
 [[package]]
 name = "playwright"
 version = "1.56.0"
@@ -925,19 +1048,31 @@ version = "1.17.0"
 description = "Python 2 and 3 compatibility utilities"
 optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,>=2.7"
-groups = ["main"]
+groups = ["main", "dev"]
 files = [
     {file = "six-1.17.0-py2.py3-none-any.whl", hash = "sha256:4721f391ed90541fddacab5acf947aa0d3dc7d27b2e1e8eda2be8970586c3274"},
     {file = "six-1.17.0.tar.gz", hash = "sha256:ff70335d468e7eb6ec65b95b99d3a2836546063f63acc5171de367e834932a81"},
 ]
 
+[[package]]
+name = "soupsieve"
+version = "2.8"
+description = "A modern CSS selector implementation for Beautiful Soup."
+optional = false
+python-versions = ">=3.9"
+groups = ["dev"]
+files = [
+    {file = "soupsieve-2.8-py3-none-any.whl", hash = "sha256:0cc76456a30e20f5d7f2e14a98a4ae2ee4e5abdc7c5ea0aafe795f344bc7984c"},
+    {file = "soupsieve-2.8.tar.gz", hash = "sha256:e2dd4a40a628cb5f28f6d4b0db8800b8f581b65bb380b97de22ba5ca8d72572f"},
+]
+
 [[package]]
 name = "sqlparse"
 version = "0.5.3"
 description = "A non-validating SQL parser."
 optional = false
 python-versions = ">=3.8"
-groups = ["main"]
+groups = ["main", "dev"]
 files = [
     {file = "sqlparse-0.5.3-py3-none-any.whl", hash = "sha256:cf2196ed3418f3ba5de6af7e82c694a9fbdbfecccdfc72e281548517081f16ca"},
     {file = "sqlparse-0.5.3.tar.gz", hash = "sha256:09f67787f56a0b16ecdbde1bfc7f5d9c3371ca683cfeaa8e6ff60b4807ec9272"},
@@ -965,7 +1100,7 @@ version = "2025.2"
 description = "Provider of IANA time zone data"
 optional = false
 python-versions = ">=2"
-groups = ["main"]
+groups = ["main", "dev"]
 markers = "sys_platform == \"win32\""
 files = [
     {file = "tzdata-2025.2-py2.py3-none-any.whl", hash = "sha256:1a403fada01ff9221ca8044d701868fa132215d84beb92242d9acd2147f667a8"},
@@ -1007,5 +1142,5 @@ brotli = ["brotli"]
 
 [metadata]
 lock-version = "2.1"
-python-versions = ">=3.13"
-content-hash = "562d9f8ae2d248b4f1bda653611b89a61217cd2f39d239f1f25f94a9821e0719"
+python-versions = ">=3.13, <4.0"
+content-hash = "58d4e82d0b07b8f145858201e771c7050debede65a9617e874d8311c4158f74c"
diff --git a/pyproject.toml b/pyproject.toml
index bf6c4d8a..250d579b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,7 @@ description = ""
 authors = [{name = "Your Name",email = "you@example.com"}]
 license = { text = "MIT" }
 readme = "README.md"
-requires-python = ">=3.13"
+requires-python = ">=3.13, <4.0"
 dependencies = [
     "azure-identity (>=1.23.0,<2.0.0)",
     "django (>=5.2.4,<6.0.0)",
@@ -23,8 +23,11 @@ package-mode = false
 ruff = "^0.14.5"
 playwright = "^1.56.0"
 axe-playwright-python = "^0.1.6"
-
+behave-django = "^1.8.0"
 
 [build-system]
 requires = ["poetry-core>=2.0.0,<3.0.0"]
 build-backend = "poetry.core.masonry.api"
+
+[tool.behave]
+paths = ["tests/features"]
diff --git a/scripts/tests/ui.sh b/scripts/tests/ui.sh
new file mode 100755
index 00000000..a599bcda
--- /dev/null
+++ b/scripts/tests/ui.sh
@@ -0,0 +1 @@
+docker compose run --rm web poetry run python manage.py behave --settings=lung_cancer_screening.settings_test
diff --git a/tests/features/cannot_change_answers_after_submission.feature b/tests/features/cannot_change_answers_after_submission.feature
new file mode 100644
index 00000000..929fb311
--- /dev/null
+++ b/tests/features/cannot_change_answers_after_submission.feature
@@ -0,0 +1,7 @@
+Feature: Participants with submitted responses
+  Scenario: Cannot change responses once submitted
+    Given I have already submitted my responses
+    When I go to "/start"
+    And I submit my participant id
+    Then I am on "/start"
+    And I see an error summary "Responses have already been submitted for this participant"
diff --git a/tests/features/environment.py b/tests/features/environment.py
new file mode 100644
index 00000000..d34a343c
--- /dev/null
+++ b/tests/features/environment.py
@@ -0,0 +1,65 @@
+"""
+Behave environment setup for Django tests.
+behave-django handles test database setup automatically.
+We just need to add live server and Playwright setup.
+"""
+import os
+from django.contrib.staticfiles.testing import StaticLiveServerTestCase  # noqa: E402
+from playwright.sync_api import sync_playwright  # noqa: E402
+
+# behave-django automatically handles:
+# - Django setup
+# - Test database creation
+# - Database transactions per scenario
+
+
+class LiveServer(StaticLiveServerTestCase):
+    """Live server for Behave tests - extends Django's StaticLiveServerTestCase."""
+
+    @classmethod
+    def setUpClass(cls):
+        """Set up live server - called once for all scenarios."""
+        super().setUpClass()
+        os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
+
+
+def before_all(context):
+    """Set up before all tests run."""
+    # Set up live server (behave-django handles test database)
+    LiveServer.setUpClass()
+    context.live_server_url = LiveServer.live_server_url
+    context.live_server_class = LiveServer
+
+    # Set up Playwright browser
+    os.environ["DJANGO_ALLOW_ASYNC_UNSAFE"] = "true"
+    context.playwright = sync_playwright().start()
+    context.browser = context.playwright.chromium.launch(headless=True)
+
+
+def after_all(context):
+    """Clean up after all tests run."""
+    # Clean up Playwright
+    if hasattr(context, 'browser'):
+        context.browser.close()
+    if hasattr(context, 'playwright'):
+        context.playwright.stop()
+
+    # Tear down live server (behave-django handles test database teardown)
+    if hasattr(context, 'live_server_class'):
+        LiveServer.tearDownClass()
+
+
+def before_scenario(context, _scenario):
+    """Set up before each scenario."""
+    # behave-django automatically handles database transactions per scenario
+    context.page = context.browser.new_page()
+
+
+def after_scenario(context, _scenario):
+    """Clean up after each scenario."""
+    # Close the page if it exists
+    if hasattr(context, 'page'):
+        context.page.close()
+        del context.page
+
+    # behave-django automatically rolls back database transactions
diff --git a/tests/features/not_a_smoker_exit.feature b/tests/features/not_a_smoker_exit.feature
new file mode 100644
index 00000000..8a47fde3
--- /dev/null
+++ b/tests/features/not_a_smoker_exit.feature
@@ -0,0 +1,7 @@
+Feature: Non smokers
+  Scenario: Non smokers are not elligible
+    Given I have started the questionnaire
+    When I go to "/have-you-ever-smoked"
+    And I fill in and submit my smoking status with "No, I have never smoked"
+    Then I am on "/non-smoker-exit"
+    And I see a title "You do not need an NHS lung health check"
diff --git a/tests/features/not_in_age_range.feature b/tests/features/not_in_age_range.feature
new file mode 100644
index 00000000..5243eb11
--- /dev/null
+++ b/tests/features/not_in_age_range.feature
@@ -0,0 +1,7 @@
+Feature: Not in age range
+  Scenario: Participants outside age range are not elligible
+    Given I have started the questionnaire
+    When I go to "/date-of-birth"
+    And I fill in and submit my date of birth with "01-01-1900"
+    Then I am on "/age-range-exit"
+    And I see a title "You do not need an NHS lung health check"
diff --git a/tests/features/questionnaire.feature b/tests/features/questionnaire.feature
new file mode 100644
index 00000000..c4c1bb4a
--- /dev/null
+++ b/tests/features/questionnaire.feature
@@ -0,0 +1,57 @@
+Feature: Questionnaire
+  Scenario: The user can complete the full questionnaire
+    When I go to "/start"
+    And I submit my participant id
+    Then I am on "/have-you-ever-smoked"
+    And I see a back link to "/start"
+    When I fill in and submit my smoking status with "Yes, I used to smoke regularly"
+    Then I am on "/date-of-birth"
+    And I see a back link to "/have-you-ever-smoked"
+    When I fill in and submit my date of birth as 55 years ago
+    Then I am on "/height"
+    And I see a back link to "/date-of-birth"
+    When I fill in and submit my height with "170"
+    And I click "Back"
+    And I click "Switch to imperial"
+    When I fill in and submit my height with "5" feet and "7" inches
+    Then I am on "/weight"
+    And I see a back link to "/height"
+    When I fill in and submit my weight with "70"
+    And I click "Back"
+    And I click "Switch to stone and pounds"
+    When I fill in and submit my weight with "5" stone and "10" pounds
+    Then I am on "/sex-at-birth"
+    And I see a back link to "/weight"
+    When I fill in and submit my sex at birth with "Male"
+    Then I am on "/gender"
+    And I see a back link to "/sex-at-birth"
+    When I fill in and submit my gender with "Female"
+    Then I am on "/ethnicity"
+    And I see a back link to "/gender"
+    When I fill in and submit my ethnicity with "White"
+    Then I am on "/education"
+    And I see a back link to "/ethnicity"
+    When I click "Continue"
+    Then I am on "/respiratory-conditions"
+    And I see a back link to "/education"
+    When I fill in and submit my respiratory conditions with "Pneumonia" and "Emphysema"
+    Then I am on "/asbestos-exposure"
+    And I see a back link to "/respiratory-conditions"
+    When I fill in and submit my asbestos exposure with "No"
+    Then I am on "/cancer-diagnosis"
+    And I see a back link to "/asbestos-exposure"
+    When I click "Continue"
+    Then I am on "/family-history-lung-cancer"
+    And I see a back link to "/cancer-diagnosis"
+    When I click "Continue"
+    Then I am on "/responses"
+    And I see a back link to "/family-history-lung-cancer"
+    And I see responses "Have you ever smoked? Yes, I used to smoke regularly"
+    And I see responses "What is your date of birth?" with a date 55 years ago
+    And I see responses "What is your height? 5 feet 7 inches"
+    And I see responses "What is your weight? 5 stone 10 pounds"
+    And I see responses "What was your sex at birth? Male"
+    And I see responses "Which of these best describes you? Female"
+    And I see responses "What is your ethnic background? White"
+    And I see responses "Have you ever worked in a job where you might have been exposed to asbestos? No"
+    And I see responses "Have you ever been diagnosed with any of the following respiratory conditions? Pneumonia, Emphysema"
diff --git a/tests/features/steps/error_steps.py b/tests/features/steps/error_steps.py
new file mode 100644
index 00000000..6e508f46
--- /dev/null
+++ b/tests/features/steps/error_steps.py
@@ -0,0 +1,11 @@
+from behave import then
+from playwright.sync_api import expect
+
+
+@then(u'I see an error summary "{error_summary}"')
+def then_i_see_an_error_summary(context, error_summary):
+    expect(context.page.locator('.nhsuk-error-summary')).to_contain_text(error_summary)
+
+@then(u'I see a form error "{error_message}"')
+def then_i_see_a_form_error(context, error_message):
+    expect(context.page.locator('.nhsuk-error-message')).to_contain_text(error_message)
diff --git a/tests/features/steps/form_steps.py b/tests/features/steps/form_steps.py
new file mode 100644
index 00000000..f9efbc50
--- /dev/null
+++ b/tests/features/steps/form_steps.py
@@ -0,0 +1,86 @@
+from behave import when
+from datetime import datetime
+from dateutil.relativedelta import relativedelta
+
+
+@when('I submit my participant id')
+def when_i_submit_my_participant_id(context):
+    if not hasattr(context, 'participant_id'):
+        context.participant_id = 'abc123'
+    context.page.fill('input[name="participant_id"]', context.participant_id)
+    context.page.click('button[type="submit"]')
+
+@when('I fill in and submit my smoking status with "{smoking_status}"')
+def when_i_fill_in_and_submit_my_smoking_status(context, smoking_status):
+    context.page.get_by_label(smoking_status).check()
+    when_i_submit_the_form(context)
+
+@when('I fill in and submit my date of birth with "{date_of_birth}"')
+def when_i_fill_in_and_submit_my_date_of_birth(context, date_of_birth):
+    day, month, year = date_of_birth.split('-')
+    context.page.get_by_label('Day').fill(day)
+    context.page.get_by_label('Month').fill(month)
+    context.page.get_by_label('Year').fill(year)
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my date of birth as {years} years ago')
+def when_i_fill_in_and_submit_my_date_of_birth_as_x_years_ago(context, years):
+    date_of_birth = datetime.now() - relativedelta(years=int(years))
+    context.page.get_by_label('Day').fill(str(date_of_birth.day))
+    context.page.get_by_label('Month').fill(str(date_of_birth.month))
+    context.page.get_by_label('Year').fill(str(date_of_birth.year))
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my height with "{height}"')
+def when_i_fill_in_and_submit_my_height(context, height):
+    context.page.get_by_label('Centimetre').fill(height)
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my height with "{feet}" feet and "{inches}" inch')
+@when(u'I fill in and submit my height with "{feet}" feet and "{inches}" inches')
+def when_i_fill_in_and_submit_my_height_with_feet_and_inches(context, feet, inches):
+    context.page.get_by_label('Feet').fill(feet)
+    context.page.get_by_label('Inches').fill(inches)
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my weight with "{weight}"')
+def when_i_fill_in_and_submit_my_weight(context, weight):
+    context.page.get_by_label('Kilograms').fill(weight)
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my weight with "{stone}" stone and "{pounds}" pound')
+@when(u'I fill in and submit my weight with "{stone}" stone and "{pounds}" pounds')
+def stone_and_pounds(context, stone, pounds):
+    context.page.get_by_label('Stone').fill(stone)
+    context.page.get_by_label('Pounds').fill(pounds)
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my sex at birth with "{sex_at_birth}"')
+def when_i_fill_in_and_submit_my_sex_at_birth(context, sex_at_birth):
+    context.page.get_by_label(sex_at_birth, exact=True).check()
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my gender with "{gender}"')
+def when_i_fill_in_and_submit_my_gender(context, gender):
+    context.page.get_by_label(gender, exact=True).check()
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my ethnicity with "{ethnicity}"')
+def when_i_fill_in_and_submit_my_ethnicity(context, ethnicity):
+    context.page.get_by_label(ethnicity, exact=True).check()
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my respiratory conditions with "{condition_a}" and "{condition_b}"')
+def when_i_fill_in_and_submit_my_respiratory_conditions(context, condition_a, condition_b):
+    context.page.get_by_label(condition_a).check()
+    context.page.get_by_label(condition_b).check()
+    when_i_submit_the_form(context)
+
+@when(u'I fill in and submit my asbestos exposure with "{asbestos_exposure}"')
+def when_i_fill_in_and_submit_my_asbestos_exposure(context, asbestos_exposure):
+    context.page.get_by_label(asbestos_exposure, exact=True).check()
+    when_i_submit_the_form(context)
+
+@when('I submit the form')
+def when_i_submit_the_form(context):
+    context.page.click("text=Continue")
diff --git a/tests/features/steps/navigation_steps.py b/tests/features/steps/navigation_steps.py
new file mode 100644
index 00000000..d4427706
--- /dev/null
+++ b/tests/features/steps/navigation_steps.py
@@ -0,0 +1,15 @@
+from behave import when, then
+from playwright.sync_api import expect
+
+
+@when('I go to "{path}"')
+def given_i_go_to(context, path):
+    context.page.goto(f"{context.live_server_url}{path}")
+
+@when('I click "{text}"')
+def when_i_click(context, text):
+    context.page.click(f"text={text}")
+
+@then('I am on "{path}"')
+def then_i_am_on(context, path):
+    expect(context.page).to_have_url(f"{context.live_server_url}{path}")
diff --git a/tests/features/steps/page_assertion_steps.py b/tests/features/steps/page_assertion_steps.py
new file mode 100644
index 00000000..709ae8db
--- /dev/null
+++ b/tests/features/steps/page_assertion_steps.py
@@ -0,0 +1,25 @@
+from behave import given, then
+from playwright.sync_api import expect
+from datetime import datetime
+from dateutil.relativedelta import relativedelta
+
+@then(u'I see a title "{title}"')
+def then_i_see_a_title(context, title):
+    expect(context.page.locator('.title')).to_have_text(title)
+
+@then(u'I see a back link to "{url}"')
+def then_i_see_a_back_link_to(context, url):
+    back_link = context.page.locator(".nhsuk-back-link")
+    expect(back_link).to_have_count(1)
+    expect(back_link).to_have_attribute("href", url)
+
+@then(u'I see responses "{text}"')
+def then_i_see_responses(context, text):
+    responses = context.page.locator(".responses")
+    expect(responses).to_contain_text(text)
+
+@then(u'I see responses "{text}" with a date {years} years ago')
+def then_i_see_responses_with_a_date(context, text, years):
+    date_of_birth = datetime.now() - relativedelta(years=int(years))
+    responses = context.page.locator(".responses")
+    expect(responses).to_contain_text(f"{text} {date_of_birth.strftime('%Y-%m-%d')}")
diff --git a/tests/features/steps/participant_steps.py b/tests/features/steps/participant_steps.py
new file mode 100644
index 00000000..1db7711d
--- /dev/null
+++ b/tests/features/steps/participant_steps.py
@@ -0,0 +1,25 @@
+from behave import given
+from django.utils import timezone
+from lung_cancer_screening.questions.models.participant import Participant
+
+
+@given('a participant {participant_id} exists')
+@given('the participant {participant_id} exists')
+def given_a_participant_exists(context, participant_id):
+    Participant.objects.create(unique_id=participant_id)
+
+
+@given('I have already submitted my responses')
+def given_i_have_already_submitted_my_responses(context):
+    context.participant_id = 'abc123'
+    participant = Participant.objects.create(unique_id=context.participant_id)
+    participant.responseset_set.create(
+        submitted_at=timezone.now()
+    )
+
+@given('I have started the questionnaire')
+def given_i_have_started_the_questionnaire(context):
+    context.participant_id = 'abc123'
+    context.page.goto(f'{context.live_server_url}/start')
+    context.page.fill('input[name="participant_id"]', context.participant_id)
+    context.page.click('button[type="submit"]')
diff --git a/tests/features/validation_errors.feature b/tests/features/validation_errors.feature
new file mode 100644
index 00000000..3f7b26ea
--- /dev/null
+++ b/tests/features/validation_errors.feature
@@ -0,0 +1,99 @@
+Feature: Validation errors
+  Scenario: Date of birth form errors
+    Given I have started the questionnaire
+    When I go to "/date-of-birth"
+    And I submit the form
+    Then I am on "/date-of-birth"
+    And I see a form error "Enter your date of birth."
+
+  Scenario: Height form errors
+    Given I have started the questionnaire
+    When I go to "/height"
+    And I submit the form
+    Then I am on "/height"
+    And I see a form error "Enter your height."
+    When I fill in and submit my height with "139.6"
+    Then I am on "/height"
+    And I see a form error "Height must be between 139.7cm and 243.8 cm"
+    When I fill in and submit my height with "243.9"
+    Then I am on "/height"
+    And I see a form error "Height must be between 139.7cm and 243.8 cm"
+
+  Scenario: Height imperial form errors
+    Given I have started the questionnaire
+    When I go to "/height?unit=imperial"
+    And I submit the form
+    Then I am on "/height?unit=imperial"
+    And I see a form error "Enter your height."
+    When I fill in and submit my height with "5.2" feet and "2" inches
+    Then I am on "/height?unit=imperial"
+    And I see a form error "Feet must be in whole numbers"
+    When I fill in and submit my height with "5" feet and "2.2" inches
+    Then I am on "/height?unit=imperial"
+    And I see a form error "Inches must be in whole numbers"
+    When I fill in and submit my height with "8" feet and "1" inch
+    Then I am on "/height?unit=imperial"
+    And I see a form error "Height must be between 4 feet 7 inches and 8 feet"
+
+  Scenario: Weight form errors
+    Given I have started the questionnaire
+    When I go to "/weight"
+    And I submit the form
+    Then I am on "/weight"
+    And I see a form error "Enter your weight."
+    When I fill in and submit my weight with "25.3"
+    Then I am on "/weight"
+    And I see a form error "Weight must be between 25.4kg and 317.5kg"
+    When I fill in and submit my weight with "317.6"
+    Then I am on "/weight"
+    And I see a form error "Weight must be between 25.4kg and 317.5kg"
+
+  Scenario: Weight imperial form errors
+    Given I have started the questionnaire
+    When I go to "/weight?unit=imperial"
+    And I submit the form
+    Then I am on "/weight?unit=imperial"
+    And I see a form error "Enter your weight."
+    When I fill in and submit my weight with "5.2" stone and "2" pounds
+    Then I am on "/weight?unit=imperial"
+    And I see a form error "Stone must be in whole numbers"
+    When I fill in and submit my weight with "5" stone and "2.2" pounds
+    Then I am on "/weight?unit=imperial"
+    And I see a form error "Pounds must be in whole numbers"
+    When I fill in and submit my weight with "3" stone and "12" pounds
+    Then I am on "/weight?unit=imperial"
+    And I see a form error "Weight must be between 4 stone and 50 stone"
+    When I fill in and submit my weight with "50" stone and "1" pound
+    Then I am on "/weight?unit=imperial"
+    And I see a form error "Weight must be between 4 stone and 50 stone"
+
+  Scenario: Sex at birth form errors
+    Given I have started the questionnaire
+    When I go to "/sex-at-birth"
+    And I submit the form
+    Then I am on "/sex-at-birth"
+    And I see a form error "Select your sex at birth."
+
+  Scenario: Gender form errors
+    Given I have started the questionnaire
+    When I go to "/gender"
+    And I submit the form
+    Then I am on "/gender"
+    And I see a form error "Select the option that best describes your gender."
+
+  Scenario: Ethnicity form errors
+    Given I have started the questionnaire
+    When I go to "/ethnicity"
+    And I submit the form
+    Then I am on "/ethnicity"
+    And I see a form error "Select your ethnic background."
+
+  Scenario: Respiratory conditions form errors
+    Given I have started the questionnaire
+    When I go to "/respiratory-conditions"
+    And I submit the form
+    Then I am on "/respiratory-conditions"
+    And I see a form error "Select if you have had any respiratory conditions"
+    When I fill in and submit my respiratory conditions with "Bronchitis" and "No, I have not had any of these respiratory conditions"
+    Then I am on "/respiratory-conditions"
+    And I see a form error "Select if you have had any respiratory conditions, or select 'No, I have not had any of these respiratory conditions'"