diff --git a/src/yang/etsi-nfv-common.yang b/src/yang/etsi-nfv-common.yang
index 7077b5c7b1018057b7c02829dc02f44a51e76dd7..4c5356d84c583a3929b14fd6edc7297349a07d1e 100644
--- a/src/yang/etsi-nfv-common.yang
+++ b/src/yang/etsi-nfv-common.yang
@@ -393,6 +393,14 @@ submodule etsi-nfv-common {
     }
   }
 
+  typedef external-lifecycle-management-script-event {
+    type enumeration {
+      enum "vnf-snapshot-creation";
+      enum "vnf-snapshot-reverting-to";
+      enum "change-current-vnf-package";
+    }
+  }
+
   grouping local-affinity-or-anti-affinity-rule {
     list local-affinity-or-anti-affinity-rule {
       key "type scope";