diff --git a/include/osmocom/msc/gsm_09_11.h b/include/osmocom/msc/gsm_09_11.h
index 4e7a5b6..5e689fb 100644
--- a/include/osmocom/msc/gsm_09_11.h
+++ b/include/osmocom/msc/gsm_09_11.h
@@ -1,5 +1,7 @@
 #pragma once
 
 #include <osmocom/core/msgb.h>
+#include <osmocom/gsm/gsup.h>
 
 int gsm0911_rcv_nc_ss(struct gsm_subscriber_connection *conn, struct msgb *msg);
+int gsm0911_gsup_handler(struct vlr_subscr *vsub, struct osmo_gsup_message *gsup);