diff --git a/atst/domain/environments.py b/atst/domain/environments.py
index be007740..853eadb7 100644
--- a/atst/domain/environments.py
+++ b/atst/domain/environments.py
@@ -1,5 +1,6 @@
 from atst.database import db
 from atst.models.environment import Environment
+from atst.models.environment_role import EnvironmentRole, CSPRole
 
 
 class Environments(object):
@@ -16,3 +17,13 @@ class Environments(object):
             environment = Environment(project=project, name=name)
             db.session.add(environment)
         db.session.commit()
+
+    @classmethod
+    def add_member(cls, user, environment, member):
+        environment_user = EnvironmentRole(
+            user=member, environment=environment, role=CSPRole.NONSENSE_ROLE.value
+        )
+        db.session.add(environment_user)
+        db.session.commit()
+
+        return environment
diff --git a/atst/models/environment.py b/atst/models/environment.py
index 8e812635..d58ef270 100644
--- a/atst/models/environment.py
+++ b/atst/models/environment.py
@@ -14,3 +14,7 @@ class Environment(Base, TimestampsMixin):
 
     project_id = Column(ForeignKey("projects.id"))
     project = relationship("Project")
+
+    @property
+    def users(self):
+        return [r.user for r in self.roles]
diff --git a/tests/models/test_environments.py b/tests/models/test_environments.py
new file mode 100644
index 00000000..11dc6408
--- /dev/null
+++ b/tests/models/test_environments.py
@@ -0,0 +1,16 @@
+from atst.domain.environments import Environments
+from atst.domain.workspaces import Workspaces
+from atst.domain.projects import Projects
+from tests.factories import RequestFactory, UserFactory
+
+
+def test_add_user_to_environment():
+    owner = UserFactory.create()
+    developer = UserFactory.from_atat_role("developer")
+
+    workspace = Workspaces.create(RequestFactory.create(creator=owner))
+    project = Projects.create(workspace, "my test project", "It's mine.", ["dev", "staging", "prod"])
+    dev_environment = project.environments[0]
+
+    dev_environment = Environments.add_member(owner, dev_environment, developer)
+    assert developer in dev_environment.users