diff --git a/src/sgsn/sgsn_cdr.c b/src/sgsn/sgsn_cdr.c
index db32644..1536c13 100644
--- a/src/sgsn/sgsn_cdr.c
+++ b/src/sgsn/sgsn_cdr.c
@@ -29,6 +29,7 @@
 #include <osmocom/sgsn/vty.h>
 #include <osmocom/sgsn/gtp_ggsn.h>
 #include <osmocom/sgsn/pdpctx.h>
+#include <osmocom/sgsn/mmctx.h>
 
 #include <gtp.h>
 #include <pdp.h>