diff --git a/libp2p/network/network_interface.py b/libp2p/network/network_interface.py
index 1867efc..acd20b1 100644
--- a/libp2p/network/network_interface.py
+++ b/libp2p/network/network_interface.py
@@ -41,3 +41,9 @@ class INetwork(ABC):
         :param *args: one or many multiaddrs to start listening on
         :return: True if at least one success
         """
+
+    @abstractmethod
+    def notify(self, notifee):
+        """
+        :param notifee: object implementing Notifee interface
+        """