diff --git a/Alc/backends/null.c b/Alc/backends/null.c
index 0b58310a..93b38063 100644
--- a/Alc/backends/null.c
+++ b/Alc/backends/null.c
@@ -21,6 +21,9 @@
 #include "config.h"
 
 #include <stdlib.h>
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+#endif
 
 #include "alMain.h"
 #include "alu.h"
diff --git a/Alc/backends/wave.c b/Alc/backends/wave.c
index ecbfde66..38932819 100644
--- a/Alc/backends/wave.c
+++ b/Alc/backends/wave.c
@@ -23,6 +23,9 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <memory.h>
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+#endif
 
 #include "alMain.h"
 #include "alu.h"
diff --git a/OpenAL32/Include/alMain.h b/OpenAL32/Include/alMain.h
index 8b0850de..ba6a5c8b 100644
--- a/OpenAL32/Include/alMain.h
+++ b/OpenAL32/Include/alMain.h
@@ -107,6 +107,7 @@ static const union {
 
 #ifdef _WIN32
 
+#define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 
 typedef DWORD pthread_key_t;