diff --git a/lesson_15/tdd/tdd_app/src/main/java/com/codedifferently/lesson15/Employee.java b/lesson_15/tdd/tdd_app/src/main/java/com/codedifferently/lesson15/Employee.java
index 49aaabbd7..a3b32a29f 100644
--- a/lesson_15/tdd/tdd_app/src/main/java/com/codedifferently/lesson15/Employee.java
+++ b/lesson_15/tdd/tdd_app/src/main/java/com/codedifferently/lesson15/Employee.java
@@ -45,4 +45,8 @@ public double getSalary() {
   public void setSalary(double salary) {
     this.salary = salary;
   }
+
+  public String getDetails() {
+    return "ID:" + id + "Name: " + name + "Department: " + department + "salary: " + salary;
+  }
 }
diff --git a/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeManagerTest.java b/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeManagerTest.java
new file mode 100644
index 000000000..95f62dd43
--- /dev/null
+++ b/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeManagerTest.java
@@ -0,0 +1,72 @@
+package com.codedifferently.lesson15;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class EmployeeManagerTest {
+
+  EmployeeManager employeeManager;
+
+  Employee employee;
+
+  @BeforeEach
+  public void setUp() {
+    employeeManager = new EmployeeManager();
+    employee = new Employee(2, "Hummad", "Finance", 2000);
+  }
+
+  @Test
+  public void testAddEmployee() {
+
+    employeeManager.addEmployee(employee);
+    Employee employee1 = new Employee(3, "Hummad", "Finance", 2000);
+    employeeManager.addEmployee(employee1);
+
+    assertEquals(2, employeeManager.getEmployeeCount());
+  }
+
+  @Test
+  public void testGetEmployee() {
+
+    employeeManager.addEmployee(employee);
+
+    assertEquals(employee, employeeManager.getEmployee(employee.getId()));
+  }
+
+  @Test
+  public void testGetEmployeeCount() {
+
+    employee = new Employee(2, "Hummad", "Finance", 2000);
+    Employee employee1 = new Employee(3, "Hummad", "Finance", 2000);
+
+    employeeManager.addEmployee(employee1);
+
+    employeeManager.addEmployee(employee);
+
+    assertEquals(2, employeeManager.getEmployeeCount());
+  }
+
+  @Test
+  public void testRemoveEmployee() {
+
+    employeeManager.addEmployee(employee);
+
+    employeeManager.removeEmployee(employee.getId());
+
+    assertEquals(0, employeeManager.getEmployeeCount());
+  }
+
+  @Test
+  public void testUpdateEmployee() {
+
+    employee = new Employee(2, "Hummad", "Finance", 2000);
+
+    employeeManager.addEmployee(employee);
+
+    employeeManager.updateEmployee(employee);
+
+    assertEquals(employeeManager.getEmployee(employee.getId()), employee);
+  }
+}
diff --git a/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeTest.java b/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeTest.java
new file mode 100644
index 000000000..507466488
--- /dev/null
+++ b/lesson_15/tdd/tdd_app/src/test/java/com/codedifferently/lesson15/EmployeeTest.java
@@ -0,0 +1,74 @@
+package com.codedifferently.lesson15;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class EmployeeTest {
+
+  Employee employee;
+
+  @BeforeEach
+  void setUp() {
+    employee = new Employee(2, "Hummad", "Finance", 2000);
+  }
+
+  @Test
+  public void testGetId() {
+
+    int actualId = 2;
+    int expectedId = employee.getId();
+    assertEquals(expectedId, actualId);
+  }
+
+  @Test
+  public void testGetSalary() {
+    assertEquals(employee.getSalary(), 2000);
+  }
+
+  @Test
+  public void testSetSalary() {
+    employee.setSalary(2000);
+    assertEquals(employee.getSalary(), 2000);
+  }
+
+  @Test
+  public void testSetId() {
+
+    employee.setId(10);
+    assertEquals(employee.getId(), 10);
+  }
+
+  @Test
+  public void testGetName() {
+    employee.getName();
+    assertEquals(employee.getName(), "Hummad");
+  }
+
+  @Test
+  public void testSetName() {
+    employee.setName("Hummad");
+    assertEquals(employee.getName(), "Hummad");
+  }
+
+  @Test
+  public void testGetDepartment() {
+
+    assertEquals(employee.getDepartment(), "Finance");
+  }
+
+  @Test
+  public void testSetDepartment() {
+
+    employee.setDepartment("Finance");
+    assertEquals(employee.getDepartment(), "Finance");
+  }
+
+  @Test
+  public void testGetDetails() {
+
+    // String expectedDetails = "2 Hummad Finance 2000";
+    assertEquals("ID:2Name: HummadDepartment: Financesalary: 2000.0", employee.getDetails());
+  }
+}