diff --git a/atst/models/user.py b/atst/models/user.py
index 83f34326..3f980453 100644
--- a/atst/models/user.py
+++ b/atst/models/user.py
@@ -80,6 +80,9 @@ class User(
     def displayname(self):
         return self.full_name
 
+    def is_app_member(self, application):
+        return self in application.users
+
     def __repr__(self):
         return "<User(name='{}', dod_id='{}', email='{}', has_portfolios='{}', id='{}')>".format(
             self.full_name, self.dod_id, self.email, self.has_portfolios, self.id
diff --git a/tests/models/test_user.py b/tests/models/test_user.py
index 2a3ae51e..438c53e6 100644
--- a/tests/models/test_user.py
+++ b/tests/models/test_user.py
@@ -26,6 +26,19 @@ def test_cannot_update_dod_id(session):
         session.commit()
 
 
+def test_is_app_member():
+    user = UserFactory.create()
+    app = ApplicationFactory.create()
+    ApplicationRoleFactory.create(user=user, application=app)
+    assert user.is_app_member(app)
+
+
+def test_is_not_app_member():
+    user = UserFactory.create()
+    app = ApplicationFactory.create()
+    assert not user.is_app_member(app)
+
+
 def test_deleted_application_roles_are_ignored(session):
     user = UserFactory.create()
     app = ApplicationFactory.create()