diff --git a/dlls/dwmapi/dwmapi.spec b/dlls/dwmapi/dwmapi.spec
index 7c613d0ad4..ea41e0cfeb 100644
--- a/dlls/dwmapi/dwmapi.spec
+++ b/dlls/dwmapi/dwmapi.spec
@@ -23,7 +23,7 @@
 @ stub DwmAttachMilContent
 @ stub DwmDefWindowProc
 @ stub DwmDetachMilContent
-@ stub DwmEnableBlurBehindWindow
+@ stdcall DwmEnableBlurBehindWindow(ptr ptr)
 @ stdcall DwmEnableMMCSS(long)
 @ stdcall DwmExtendFrameIntoClientArea(long ptr)
 @ stdcall DwmFlush()
diff --git a/dlls/dwmapi/dwmapi_main.c b/dlls/dwmapi/dwmapi_main.c
index ee866912a3..fcc52c3826 100644
--- a/dlls/dwmapi/dwmapi_main.c
+++ b/dlls/dwmapi/dwmapi_main.c
@@ -166,3 +166,13 @@ HRESULT WINAPI DwmGetGraphicsStreamTransformHint(UINT uIndex, MilMatrix3x2D *pTr
 
     return E_NOTIMPL;
 }
+
+/**********************************************************************
+ *           DwmEnableBlurBehindWindow         (DWMAPI.@)
+ */
+HRESULT WINAPI DwmEnableBlurBehindWindow(HWND hWnd, const DWM_BLURBEHIND *pBlurBuf)
+{
+    FIXME("%p %p\n", hWnd, pBlurBuf);
+
+    return E_NOTIMPL;
+}
diff --git a/include/dwmapi.h b/include/dwmapi.h
index 4fe51bcdbe..2cf5d6df8f 100644
--- a/include/dwmapi.h
+++ b/include/dwmapi.h
@@ -41,6 +41,19 @@ typedef struct _MilMatrix3x2D
     DOUBLE DY;
 } MilMatrix3x2D;
 
+#define DWM_BB_ENABLE                 0x00000001
+#define DWM_BB_BLURREGION             0x00000002
+#define DWM_BB_TRANSITIONONMAXIMIZED  0x00000004
+
+typedef struct _DWM_BLURBEHIND
+{
+    DWORD dwFlags;
+    BOOL fEnable;
+    HRGN hRgnBlur;
+    BOOL fTransitionOnMaximized;
+} DWM_BLURBEHIND, *PDWM_BLURBEHIND;
+
+DWMAPI DwmEnableBlurBehindWindow(HWND, const DWM_BLURBEHIND *);
 DWMAPI DwmEnableComposition(UINT);
 DWMAPI DwmEnableMMCSS(BOOL);
 DWMAPI DwmExtendFrameIntoClientArea(HWND,const MARGINS*);