diff --git a/colab/signals/signals.py b/colab/signals/signals.py
index e35f74c..6caeb1a 100644
--- a/colab/signals/signals.py
+++ b/colab/signals/signals.py
@@ -29,3 +29,5 @@ class Signals():
     def send(self, signal_name, sender, **kwargs):
         if signal_name in self.signal_instances:
             self.signal_instances[signal_name].send(sender=sender)
+        else:
+            raise Exception("Signal does not exist!")
diff --git a/colab/signals/tests/test_signals.py b/colab/signals/tests/test_signals.py
index b75c49a..be872e8 100644
--- a/colab/signals/tests/test_signals.py
+++ b/colab/signals/tests/test_signals.py
@@ -79,4 +79,5 @@ class SignalsTest(TestCase):
         self.assertTrue(mock.is_called)
         
 
-
+    def test_send_signal_not_registered(self):
+        self.assertRaises(Exception, self.signals.send, 'test_signal', 'test')
--
libgit2 0.21.2