diff --git a/lib/icinga/icinga-type.conf b/lib/icinga/icinga-type.conf
index d59cd95d9..473f4b938 100644
--- a/lib/icinga/icinga-type.conf
+++ b/lib/icinga/icinga-type.conf
@@ -143,6 +143,7 @@ type Notification {
 		%attribute number "end",
 	},
 
+	%require "notification_command",
 	%attribute name(NotificationCommand) "notification_command",
 
 	%attribute number "notification_interval",