diff --git a/picasso/api/controllers/runnable.py b/picasso/api/controllers/runnable.py
index 6ab9610..338ac21 100644
--- a/picasso/api/controllers/runnable.py
+++ b/picasso/api/controllers/runnable.py
@@ -139,9 +139,19 @@ class RunnableV1Controller(controller.ServiceController,
             "200":
                 description: successful operation. Return "runnable" JSON
             "404":
-                description: App does not exist
+                description: App not found
             "404":
-                description: App route does not exist
+                description: App route not found
         """
+        app = request.match_info.get('app')
+        project_id = request.match_info.get('project_id')
+
+        if not (await app_model.Apps.exists(app, project_id)):
+            return web.json_response(data={
+                "error": {
+                    "message": "App {0} not found".format(app),
+                }
+            }, status=404)
+
         return await super(RunnableV1Controller,
                            self).run(request, **kwargs)
diff --git a/picasso/tests/common/routes.py b/picasso/tests/common/routes.py
index d70077b..ab76c59 100644
--- a/picasso/tests/common/routes.py
+++ b/picasso/tests/common/routes.py
@@ -223,3 +223,13 @@ class AppRoutesTestSuite(object):
                 )
             )
             self.assertEqual(403, status)
+
+    def fail_to_run_app_from_other_project(self):
+        with setup_execute(self, "fail_to_run_app_"
+                                 "from_other_project") as app_name:
+            _, status = self.testloop.run_until_complete(
+                self.other_test_client.routes.execute_public(
+                    app_name, self.route_data["path"]
+                )
+            )
+            self.assertEqual(404, status)
diff --git a/picasso/tests/functional/base.py b/picasso/tests/functional/base.py
index cf88952..4e3db03 100644
--- a/picasso/tests/functional/base.py
+++ b/picasso/tests/functional/base.py
@@ -74,12 +74,17 @@ class FunctionalTestsBase(base.PicassoTestsBase, testtools.TestCase):
         )
 
         self.project_id = str(uuid.uuid4()).replace("-", "")
+        self.other_project_id = str(uuid.uuid4()).replace("-", "")
+
         self.test_client = client.ProjectBoundTestClient(
             self.testapp, self.project_id)
+        self.other_test_client = client.ProjectBoundTestClient(
+            self.testapp, self.other_project_id)
 
         self.testloop.run_until_complete(self.test_client.start_server())
         super(FunctionalTestsBase, self).setUp()
 
     def tearDown(self):
         self.testloop.run_until_complete(self.test_client.close())
+        self.testloop.run_until_complete(self.other_test_client.close())
         super(FunctionalTestsBase, self).tearDown()
diff --git a/picasso/tests/functional/test_routes.py b/picasso/tests/functional/test_routes.py
index 0869c54..ee48539 100644
--- a/picasso/tests/functional/test_routes.py
+++ b/picasso/tests/functional/test_routes.py
@@ -52,3 +52,7 @@ class TestAppRoutes(base.FunctionalTestsBase,
 
     def test_fail_to_execute_private_route(self):
         super(TestAppRoutes, self).fail_to_execute_private_as_public()
+
+    def test_fail_to_run_app_from_other_project(self):
+        super(TestAppRoutes,
+              self).fail_to_run_app_from_other_project()