diff --git a/src/MultiPlayer/multiplaymgr.hxx b/src/MultiPlayer/multiplaymgr.hxx
index daae68b57..42444f014 100644
--- a/src/MultiPlayer/multiplaymgr.hxx
+++ b/src/MultiPlayer/multiplaymgr.hxx
@@ -34,6 +34,7 @@
 
 #include <string>
 #include <vector>
+#include <memory>
 
 #include <simgear/compiler.h>
 #include <simgear/props/props.hxx>