diff --git a/common/fltk/FL/Fl_Window.H b/common/fltk/FL/Fl_Window.H
index 02ba688..9632895 100644
--- a/common/fltk/FL/Fl_Window.H
+++ b/common/fltk/FL/Fl_Window.H
@@ -31,6 +31,10 @@
 #ifndef Fl_Window_H
 #define Fl_Window_H
 
+#ifdef WIN32
+#include <windows.h>
+#endif
+
 #include "Fl_Group.H"
 
 #define FL_WINDOW 0xF0		///< window type id all subclasses have type() >= this
@@ -63,9 +67,19 @@
   friend class Fl_X;
   Fl_X *i; // points at the system-specific stuff
 
+  struct icon_data {
+    const void *legacy_icon;
+    Fl_RGB_Image **icons;
+    int count;
+#ifdef WIN32
+    HICON big_icon;
+    HICON small_icon;
+#endif
+  };
+
   const char* iconlabel_;
   char* xclass_;
-  const void* icon_;
+  struct icon_data *icon_;
   // size_range stuff:
   int minw, minh, maxw, maxh;
   int dw, dh, aspect;
@@ -110,6 +124,8 @@
   */
   int force_position() const { return ((flags() & FORCE_POSITION)?1:0); }
 
+  void free_icons();
+
 public:
 
   /**
@@ -331,6 +347,18 @@
   static const char *default_xclass();
   const char* xclass() const;
   void xclass(const char* c);
+
+  static void default_icon(const Fl_RGB_Image*);
+  static void default_icons(const Fl_RGB_Image*[], int);
+  void icon(const Fl_RGB_Image*);
+  void icons(const Fl_RGB_Image*[], int);
+
+#ifdef WIN32
+  static void default_icons(HICON big_icon, HICON small_icon);
+  void icons(HICON big_icon, HICON small_icon);
+#endif
+
+  /* for legacy compatibility */
   const void* icon() const;
   void icon(const void * ic);
 
diff --git a/common/fltk/FL/mac.H b/common/fltk/FL/mac.H
index f23dc8e..97eefd8 100644
--- a/common/fltk/FL/mac.H
+++ b/common/fltk/FL/mac.H
@@ -141,6 +141,9 @@
   void collapse(void);
   WindowRef window_ref(void);
   void set_key_window(void);
+  // OS X doesn't have per window icons
+  static void set_default_icons(const Fl_RGB_Image*[], int) {};
+  void set_icons() {};
   int set_cursor(Fl_Cursor);
   int set_cursor(const Fl_RGB_Image*, int, int);
   static CGImageRef CGImage_from_window_rect(Fl_Window *win, int x, int y, int w, int h);
diff --git a/common/fltk/FL/win32.H b/common/fltk/FL/win32.H
index 9297e9f..858fe5b 100644
--- a/common/fltk/FL/win32.H
+++ b/common/fltk/FL/win32.H
@@ -93,6 +93,9 @@
   void flush() {w->flush();}
   void set_minmax(LPMINMAXINFO minmax);
   void mapraise();
+  static void set_default_icons(const Fl_RGB_Image*[], int);
+  static void set_default_icons(HICON, HICON);
+  void set_icons();
   int set_cursor(Fl_Cursor);
   int set_cursor(const Fl_RGB_Image*, int, int);
   static Fl_X* make(Fl_Window*);
diff --git a/common/fltk/FL/x.H b/common/fltk/FL/x.H
index a520286..c2eb46e 100644
--- a/common/fltk/FL/x.H
+++ b/common/fltk/FL/x.H
@@ -163,6 +163,8 @@
   static Fl_X* i(const Fl_Window* wi) {return wi->i;}
   void setwindow(Fl_Window* wi) {w=wi; wi->i=this;}
   void sendxjunk();
+  static void set_default_icons(const Fl_RGB_Image*[], int);
+  void set_icons();
   int set_cursor(Fl_Cursor);
   int set_cursor(const Fl_RGB_Image*, int, int);
   static void make_xid(Fl_Window*,XVisualInfo* =fl_visual, Colormap=fl_colormap);