diff --git a/repmgr.c b/repmgr.c
index 8f340e03..2eaddc6c 100644
--- a/repmgr.c
+++ b/repmgr.c
@@ -28,6 +28,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/wait.h>
 #include <time.h>
 #include <unistd.h>