diff --git a/src/linkml_reference_validator/plugins/__init__.py b/src/linkml_reference_validator/plugins/__init__.py
index eef6d6c..6a7cb14 100644
--- a/src/linkml_reference_validator/plugins/__init__.py
+++ b/src/linkml_reference_validator/plugins/__init__.py
@@ -1,7 +1,14 @@
 """LinkML validation plugins for reference validation."""
 
-from linkml_reference_validator.plugins.reference_validation_plugin import (
-    ReferenceValidationPlugin,
-)
+from importlib.util import find_spec
 
-__all__ = ["ReferenceValidationPlugin"]
+# `linkml` is an optional dependency. Expose the LinkML plugin only when LinkML is available.
+__all__: list[str]
+if find_spec("linkml") is not None and find_spec("linkml.validator") is not None:
+    from linkml_reference_validator.plugins.reference_validation_plugin import (  # noqa: F401
+        ReferenceValidationPlugin,
+    )
+
+    __all__ = ["ReferenceValidationPlugin"]
+else:
+    __all__ = []
diff --git a/tests/test_optional_linkml_dependency.py b/tests/test_optional_linkml_dependency.py
new file mode 100644
index 0000000..ca50d97
--- /dev/null
+++ b/tests/test_optional_linkml_dependency.py
@@ -0,0 +1,51 @@
+"""Tests for running without optional `linkml` dependency installed."""
+
+import importlib
+import sys
+from importlib import util as importlib_util
+
+
+def test_cli_imports_without_linkml(monkeypatch):
+    """Importing the CLI should not require `linkml` to be installed."""
+
+    real_find_spec = importlib_util.find_spec
+
+    def fake_find_spec(name: str, *args, **kwargs):  # type: ignore[no-untyped-def]
+        if name == "linkml" or name.startswith("linkml."):
+            return None
+        return real_find_spec(name, *args, **kwargs)
+
+    monkeypatch.setattr(importlib_util, "find_spec", fake_find_spec)
+
+    # Force a clean import of our package modules under the "no linkml" condition
+    for mod in list(sys.modules):
+        if mod.startswith("linkml_reference_validator"):
+            del sys.modules[mod]
+
+    cli = importlib.import_module("linkml_reference_validator.cli")
+    assert getattr(cli, "app", None) is not None
+
+
+def test_plugins_package_imports_without_linkml(monkeypatch):
+    """Importing `linkml_reference_validator.plugins` should not require `linkml`."""
+
+    real_find_spec = importlib_util.find_spec
+
+    def fake_find_spec(name: str, *args, **kwargs):  # type: ignore[no-untyped-def]
+        if name == "linkml" or name.startswith("linkml."):
+            return None
+        return real_find_spec(name, *args, **kwargs)
+
+    monkeypatch.setattr(importlib_util, "find_spec", fake_find_spec)
+
+    for mod in list(sys.modules):
+        if mod.startswith("linkml_reference_validator"):
+            del sys.modules[mod]
+
+    plugins = importlib.import_module("linkml_reference_validator.plugins")
+    assert getattr(plugins, "__all__", None) == []
+
+
+
+
+