diff --git a/include/RED4ext/TLS-inl.hpp b/include/RED4ext/TLS-inl.hpp
index 3825c34f0..3ad29626f 100644
--- a/include/RED4ext/TLS-inl.hpp
+++ b/include/RED4ext/TLS-inl.hpp
@@ -4,6 +4,8 @@
 #include <RED4ext/TLS.hpp>
 #endif
 
+#include <intrin.h>
+
 RED4EXT_INLINE RED4ext::TLS* RED4ext::TLS::Get()
 {
     return *reinterpret_cast<TLS**>(__readgsqword(0x58));