diff --git a/assignment-client/src/main.cpp b/assignment-client/src/main.cpp
index 50e4f069a5..130cca9135 100644
--- a/assignment-client/src/main.cpp
+++ b/assignment-client/src/main.cpp
@@ -10,6 +10,7 @@
 #include <errno.h>
 #include <signal.h>
 #include <sys/time.h>
+#include <sys/wait.h>
 
 #include <Assignment.h>
 #include <AudioMixer.h>