diff --git a/CHANGES b/CHANGES
index d69d9a34a..9e5443313 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3,6 +3,7 @@ CHANGES IN FLTK 1.1.7
 	- Documentation fixes (STR #571, STR #648, STR #692, STR
 	  #730, STR #744, STR #745, STR #931, STR #942, STR #960,
 	  STR #969)
+	- FLUID now supports 'size_range()' (STR #851)
 	- FLUID selection boxes now synchronised (STR #964)
 	- fl_filename_list now recognizes pathnames without trailing 
 	  slash as directions (STR #854)
diff --git a/fluid/Fl_Type.h b/fluid/Fl_Type.h
index 8220273bb..eaacb3a29 100644
--- a/fluid/Fl_Type.h
+++ b/fluid/Fl_Type.h
@@ -485,7 +485,7 @@ protected:
 
 public:
 
-  Fl_Window_Type() { drag = dx = dy = 0; }
+  Fl_Window_Type() { drag = dx = dy = 0; sr_min_w = sr_min_h = sr_max_w = sr_max_h = 0; }
   uchar modal, non_modal;
 
   Fl_Type *make();
@@ -511,6 +511,8 @@ public:
   Fl_Widget *enter_live_mode(int top=0);
   void leave_live_mode();
   void copy_properties();
+
+  int sr_min_w, sr_min_h, sr_max_w, sr_max_h;
 };
 
 class Fl_Widget_Class_Type : private Fl_Window_Type {
diff --git a/fluid/Fl_Widget_Type.cxx b/fluid/Fl_Widget_Type.cxx
index 170b0fd1d..f0ba996bf 100644
--- a/fluid/Fl_Widget_Type.cxx
+++ b/fluid/Fl_Widget_Type.cxx
@@ -1284,8 +1284,94 @@ void textcolor_cb(Fl_Button* i, void* v) {
 ////////////////////////////////////////////////////////////////
 // Kludges to the panel for subclasses:
 
+void min_w_cb(Fl_Value_Input* i, void* v) {
+  if (v == LOAD) {
+    if (!current_widget->is_window()) {i->parent()->hide(); return;}
+    i->parent()->show();
+    i->value(((Fl_Window_Type*)current_widget)->sr_min_w);
+  } else {
+    int n = i->value();
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        ((Fl_Window_Type*)current_widget)->sr_min_w = n;
+      }
+    }
+  }
+}
+
+void min_h_cb(Fl_Value_Input* i, void* v) {
+  if (v == LOAD) {
+    i->value(((Fl_Window_Type*)current_widget)->sr_min_h);
+  } else {
+    int n = i->value();
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        ((Fl_Window_Type*)current_widget)->sr_min_h = n;
+      }
+    }
+  }
+}
+
+void max_w_cb(Fl_Value_Input* i, void* v) {
+  if (v == LOAD) {
+    i->value(((Fl_Window_Type*)current_widget)->sr_max_w);
+  } else {
+    int n = i->value();
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        ((Fl_Window_Type*)current_widget)->sr_max_w = n;
+      }
+    }
+  }
+}
+
+void max_h_cb(Fl_Value_Input* i, void* v) {
+  if (v == LOAD) {
+    i->value(((Fl_Window_Type*)current_widget)->sr_max_h);
+  } else {
+    int n = i->value();
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        ((Fl_Window_Type*)current_widget)->sr_max_h = n;
+      }
+    }
+  }
+}
+
+void set_min_size_cb(Fl_Button*, void* v) {
+  if (v == LOAD) {
+  } else {
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        Fl_Window_Type *win = (Fl_Window_Type*)current_widget;
+        win->sr_min_w = win->o->w();
+        win->sr_min_h = win->o->h();
+      }
+    }
+    propagate_load(the_panel, LOAD);
+  }
+}
+
+void set_max_size_cb(Fl_Button*, void* v) {
+  if (v == LOAD) {
+  } else {
+    for (Fl_Type *o = Fl_Type::first; o; o = o->next) {
+      if (o->selected && o->is_window()) {
+        Fl_Window_Type *win = (Fl_Window_Type*)current_widget;
+        win->sr_max_w = win->o->w();
+        win->sr_max_h = win->o->h();
+      }
+    }
+    propagate_load(the_panel, LOAD);
+  }
+}
+
 void slider_size_cb(Fl_Value_Input* i, void* v) {
   if (v == LOAD) {
+    if (current_widget->is_window()) 
+      i->parent()->hide(); 
+    else
+      i->parent()->show();
     if (current_widget->is_valuator()!=2) {i->deactivate(); return;}
     i->activate();
     i->value(((Fl_Slider*)(current_widget->o))->slider_size());
@@ -1523,6 +1609,15 @@ void live_mode_cb(Fl_Button*o,void *v) {
         live_window->resizable(live_widget);
         live_window->set_modal(); // block all other UI
         live_window->callback(leave_live_mode_cb);
+        if (current_widget->is_window()) {
+          Fl_Window_Type *w = (Fl_Window_Type*)current_widget;
+          int mw = w->sr_min_w; if (mw>0) mw += 20;
+          int mh = w->sr_min_h; if (mh>0) mh += 55;
+          int MW = w->sr_max_w; if (MW>0) MW += 20; 
+          int MH = w->sr_max_h; if (MH>2) MH += 55;
+          if (mw || mh || MW || MH)
+            live_window->size_range(mw, mh, MW, MH);
+        }
         live_window->show();
       } else o->value(0);
     } else o->value(0);
diff --git a/fluid/Fl_Window_Type.cxx b/fluid/Fl_Window_Type.cxx
index 9223ae918..6ded1196f 100644
--- a/fluid/Fl_Window_Type.cxx
+++ b/fluid/Fl_Window_Type.cxx
@@ -1251,6 +1251,11 @@ void Fl_Window_Type::write_code2() {
     write_cstring(xclass);
     write_c(");\n");
   }
+  if (sr_max_w || sr_max_h) {
+    write_c("%so->size_range(%d, %d, %d, %d);\n", indent(), sr_min_w, sr_min_h, sr_max_w, sr_max_h);
+  } else if (sr_min_w || sr_min_h) {
+    write_c("%so->size_range(%d, %d);\n", indent(), sr_min_w, sr_min_h);
+  }
   write_c("%so->end();\n", indent());
   if (((Fl_Window*)o)->resizable() == o)
     write_c("%so->resizable(o);\n", indent());
@@ -1263,6 +1268,8 @@ void Fl_Window_Type::write_properties() {
   else if (non_modal) write_string("non_modal");
   if (!((Fl_Window*)o)->border()) write_string("noborder");
   if (xclass) {write_string("xclass"); write_word(xclass);}
+  if (sr_min_w || sr_min_h || sr_max_w || sr_max_h)
+    write_string("size_range {%d %d %d %d}", sr_min_w, sr_min_h, sr_max_w, sr_max_h);
   if (o->visible()) write_string("visible");
 }
 
@@ -1279,6 +1286,11 @@ void Fl_Window_Type::read_property(const char *c) {
   } else if (!strcmp(c,"xclass")) {
     storestring(read_word(),xclass);
     ((Fl_Window*)o)->xclass(xclass);
+  } else if (!strcmp(c,"size_range")) {
+    int mw, mh, MW, MH;
+    if (sscanf(read_word(),"%d %d %d %d",&mw,&mh,&MW,&MH) == 4) {
+      sr_min_w = mw; sr_min_h = mh; sr_max_w = MW; sr_max_h = MH;
+    }
   } else if (!strcmp(c,"xywh")) {
     Fl_Widget_Type::read_property(c);
     pasteoffset = 0; // make it not apply to contents
diff --git a/fluid/widget_panel.cxx b/fluid/widget_panel.cxx
index 2b16e36fa..270b33e7b 100644
--- a/fluid/widget_panel.cxx
+++ b/fluid/widget_panel.cxx
@@ -51,12 +51,12 @@ Fl_Double_Window* make_widget_panel() {
     w = o;
     o->labelsize(11);
     w->hotspot(o);
-    { Fl_Tabs* o = new Fl_Tabs(5, 5, 400, 310);
+    { Fl_Tabs* o = new Fl_Tabs(3, 5, 402, 310);
       o->selection_color((Fl_Color)4);
       o->labelsize(11);
       o->callback((Fl_Callback*)cb_);
       o->when(FL_WHEN_NEVER);
-      { Fl_Group* o = new Fl_Group(5, 25, 400, 290, "GUI");
+      { Fl_Group* o = new Fl_Group(3, 25, 402, 290, "GUI");
         o->labelsize(11);
         o->callback((Fl_Callback*)propagate_load);
         o->when(FL_WHEN_NEVER);
@@ -288,6 +288,61 @@ Fl_Double_Window* make_widget_panel() {
             }
             o->end();
           }
+          { Fl_Group* o = new Fl_Group(90, 180, 300, 20, "Size Range:");
+            o->labelfont(1);
+            o->labelsize(11);
+            o->callback((Fl_Callback*)propagate_load);
+            o->align(FL_ALIGN_LEFT);
+            o->hide();
+            { Fl_Value_Input* o = new Fl_Value_Input(90, 180, 55, 20, "Minimum Size:");
+              o->tooltip("The size of the slider.");
+              o->labelsize(11);
+              o->maximum(2048);
+              o->step(1);
+              o->textsize(11);
+              o->callback((Fl_Callback*)min_w_cb);
+              o->align(FL_ALIGN_TOP_LEFT);
+            }
+            { Fl_Value_Input* o = new Fl_Value_Input(150, 180, 55, 20);
+              o->tooltip("The minimum value of the widget.");
+              o->labelsize(11);
+              o->maximum(2048);
+              o->step(1);
+              o->textsize(11);
+              o->callback((Fl_Callback*)min_h_cb);
+              o->align(FL_ALIGN_TOP_LEFT);
+            }
+            { Fl_Button* o = new Fl_Button(210, 180, 25, 20, "set");
+              o->labelsize(11);
+              o->callback((Fl_Callback*)set_min_size_cb);
+            }
+            { Fl_Value_Input* o = new Fl_Value_Input(240, 180, 55, 20, "Maximum Size:");
+              o->tooltip("The maximum value of the widget.");
+              o->labelsize(11);
+              o->maximum(2048);
+              o->step(1);
+              o->textsize(11);
+              o->callback((Fl_Callback*)max_w_cb);
+              o->align(FL_ALIGN_TOP_LEFT);
+            }
+            { Fl_Value_Input* o = new Fl_Value_Input(300, 180, 55, 20);
+              o->tooltip("The resolution of the widget value.");
+              o->labelsize(11);
+              o->maximum(2048);
+              o->step(1);
+              o->textsize(11);
+              o->callback((Fl_Callback*)max_h_cb);
+              o->align(FL_ALIGN_TOP_LEFT);
+            }
+            { Fl_Button* o = new Fl_Button(360, 180, 25, 20, "set");
+              o->labelsize(11);
+              o->callback((Fl_Callback*)set_max_size_cb);
+            }
+            { Fl_Box* o = new Fl_Box(390, 180, 0, 20);
+              Fl_Group::current()->resizable(o);
+            }
+            o->end();
+          }
           { Shortcut_Button* o = new Shortcut_Button(90, 205, 300, 20, "Shortcut:");
             o->tooltip("The shortcut key for the widget.");
             o->box(FL_DOWN_BOX);
@@ -387,7 +442,7 @@ Fl_Double_Window* make_widget_panel() {
         o->end();
         Fl_Group::current()->resizable(o);
       }
-      { Fl_Group* o = new Fl_Group(5, 25, 400, 290, "Style");
+      { Fl_Group* o = new Fl_Group(3, 25, 402, 290, "Style");
         o->labelsize(11);
         o->callback((Fl_Callback*)propagate_load);
         o->when(FL_WHEN_NEVER);
diff --git a/fluid/widget_panel.fl b/fluid/widget_panel.fl
index fc3ed02c1..dde48e1a4 100644
--- a/fluid/widget_panel.fl
+++ b/fluid/widget_panel.fl
@@ -34,20 +34,20 @@ comment {//
 Function {make_widget_panel()} {open
 } {
   Fl_Window {} {open
-    xywh {353 184 410 355} type Double labelsize 11 hide resizable hotspot
-    code0 {o->size_range(o->w(), o->h());}
+    xywh {353 184 410 355} type Double labelsize 11 resizable hotspot
+    code0 {o->size_range(o->w(), o->h());} visible
   } {
     Fl_Tabs {} {
       callback {propagate_load((Fl_Group *)o,v);} open
-      xywh {5 5 400 310} selection_color 4 labelsize 11 when 0 resizable
+      xywh {3 5 402 310} selection_color 4 labelsize 11 when 0 resizable
     } {
       Fl_Group {} {
         label GUI
-        callback propagate_load
-        xywh {5 25 400 290} labelsize 11 when 0 resizable
+        callback propagate_load open
+        xywh {3 25 402 290} labelsize 11 when 0 resizable
       } {
         Fl_Group {} {
-          callback propagate_load
+          callback propagate_load open
           xywh {3 25 396 285} labelsize 11 resizable
         } {
           Fl_Group {} {
@@ -184,7 +184,7 @@ Function {make_widget_panel()} {open
           }
           Fl_Group {} {
             label {Values:}
-            callback propagate_load
+            callback propagate_load selected
             xywh {90 180 300 20} labelfont 1 labelsize 11 align 4
           } {
             Fl_Value_Input {} {
@@ -216,6 +216,43 @@ Function {make_widget_panel()} {open
               xywh {390 180 0 20} resizable
             }
           }
+          Fl_Group {} {
+            label {Size Range:}
+            callback propagate_load
+            xywh {90 180 300 20} labelfont 1 labelsize 11 align 4 hide
+          } {
+            Fl_Value_Input {} {
+              label {Minimum Size:}
+              callback min_w_cb
+              tooltip {The size of the slider.} xywh {90 180 55 20} labelsize 11 align 5 maximum 2048 step 1 textsize 11
+            }
+            Fl_Value_Input {} {
+              callback min_h_cb
+              tooltip {The minimum value of the widget.} xywh {150 180 55 20} labelsize 11 align 5 maximum 2048 step 1 textsize 11
+            }
+            Fl_Button {} {
+              label set
+              callback set_min_size_cb
+              xywh {210 180 25 20} labelsize 11
+            }
+            Fl_Value_Input {} {
+              label {Maximum Size:}
+              callback max_w_cb
+              tooltip {The maximum value of the widget.} xywh {240 180 55 20} labelsize 11 align 5 maximum 2048 step 1 textsize 11
+            }
+            Fl_Value_Input {} {
+              callback max_h_cb
+              tooltip {The resolution of the widget value.} xywh {300 180 55 20} labelsize 11 align 5 maximum 2048 step 1 textsize 11
+            }
+            Fl_Button {} {
+              label set
+              callback set_max_size_cb
+              xywh {360 180 25 20} labelsize 11
+            }
+            Fl_Box {} {
+              xywh {390 180 0 20} resizable
+            }
+          }
           Fl_Button {} {
             label {Shortcut:}
             callback shortcut_in_cb
@@ -290,7 +327,7 @@ Function {make_widget_panel()} {open
       Fl_Group {} {
         label Style
         callback propagate_load
-        xywh {5 25 400 290} labelsize 11 when 0 hide
+        xywh {3 25 402 290} labelsize 11 when 0 hide
       } {
         Fl_Group {} {
           callback propagate_load
@@ -489,7 +526,7 @@ Function {make_widget_panel()} {open
         }
       }
     }
-    Fl_Group {} {selected
+    Fl_Group {} {
       xywh {8 321 391 24} labelsize 11
     } {
       Fl_Box {} {
diff --git a/fluid/widget_panel.h b/fluid/widget_panel.h
index 55e4524a5..da94a50cd 100644
--- a/fluid/widget_panel.h
+++ b/fluid/widget_panel.h
@@ -60,6 +60,12 @@ extern void min_cb(Fl_Value_Input*, void*);
 extern void max_cb(Fl_Value_Input*, void*);
 extern void step_cb(Fl_Value_Input*, void*);
 extern void value_cb(Fl_Value_Input*, void*);
+extern void min_w_cb(Fl_Value_Input*, void*);
+extern void min_h_cb(Fl_Value_Input*, void*);
+extern void set_min_size_cb(Fl_Button*, void*);
+extern void max_w_cb(Fl_Value_Input*, void*);
+extern void max_h_cb(Fl_Value_Input*, void*);
+extern void set_max_size_cb(Fl_Button*, void*);
 #include "Shortcut_Button.h"
 extern void shortcut_in_cb(Shortcut_Button*, void*);
 extern void xclass_cb(Fl_Input*, void*);