diff --git a/code/FBXMeshGeometry.cpp b/code/FBXMeshGeometry.cpp
index 84fcc2ed3..be3fbd621 100644
--- a/code/FBXMeshGeometry.cpp
+++ b/code/FBXMeshGeometry.cpp
@@ -45,6 +45,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef ASSIMP_BUILD_NO_FBX_IMPORTER
 
+#include <functional>
+
 #include "FBXParser.h"
 #include "FBXDocument.h"
 #include "FBXImporter.h"
diff --git a/code/LWOAnimation.cpp b/code/LWOAnimation.cpp
index 8b998c56e..d719ef951 100644
--- a/code/LWOAnimation.cpp
+++ b/code/LWOAnimation.cpp
@@ -49,6 +49,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "AssimpPCH.h"
 #if (!defined ASSIMP_BUILD_NO_LWO_IMPORTER) && (!defined ASSIMP_BUILD_NO_LWS_IMPORTER)
 
+#include <functional>
+
 // internal headers
 #include "LWOFileData.h"
 
diff --git a/code/Vertex.h b/code/Vertex.h
index 61f7d84b7..a29211d53 100644
--- a/code/Vertex.h
+++ b/code/Vertex.h
@@ -48,6 +48,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #ifndef AI_VERTEX_H_INC
 #define AI_VERTEX_H_INC
 
+#include <functional>
 
 namespace Assimp	{