diff --git a/src/services/pam/conversation.cpp b/src/services/pam/conversation.cpp
index f8f5a09..1fb4c04 100644
--- a/src/services/pam/conversation.cpp
+++ b/src/services/pam/conversation.cpp
@@ -8,6 +8,9 @@
 #include <qtmetamacros.h>
 #include <sys/signal.h>
 #include <sys/wait.h>
+#ifdef __FreeBSD__
+#include <signal.h>
+#endif
 
 #include "../../core/logcat.hpp"
 #include "ipc.hpp"