diff --git a/lcl/comctrls.pp b/lcl/comctrls.pp
index e0b0e79f87..b77095aced 100644
--- a/lcl/comctrls.pp
+++ b/lcl/comctrls.pp
@@ -3462,6 +3462,8 @@ type
     procedure DoEndDrag(Target: TObject; X, Y: Integer); override;
     function DoMouseWheel(Shift: TShiftState; WheelDelta: Integer;
                           MousePos: TPoint): Boolean; override;
+    function DoMouseWheelHorz(Shift: TShiftState; WheelDelta: Integer;
+                          MousePos: TPoint): Boolean; override;
     procedure DoPaint; virtual;
     procedure DoPaintNode(Node: TTreeNode); virtual;
     procedure DoStartDrag(var DragObject: TDragObject); override;
diff --git a/lcl/grids.pas b/lcl/grids.pas
index 10a47f425d..e080d2ffec 100644
--- a/lcl/grids.pas
+++ b/lcl/grids.pas
@@ -982,6 +982,8 @@ type
     function  DoMouseWheel(Shift: TShiftState; WheelDelta: Integer; MousePos: TPoint): Boolean; override;
     function  DoMouseWheelDown(Shift: TShiftState; MousePos: TPoint): Boolean; override;
     function  DoMouseWheelUp(Shift: TShiftState; MousePos: TPoint): Boolean; override;
+    function  DoMouseWheelLeft(Shift: TShiftState; MousePos: TPoint): Boolean; override;
+    function  DoMouseWheelRight(Shift: TShiftState; MousePos: TPoint): Boolean; override;
     procedure DoAutoAdjustLayout(const AMode: TLayoutAdjustmentPolicy;
       const AXProportion, AYProportion: Double); override;
     procedure DoOnChangeBounds; override;
@@ -7150,6 +7152,30 @@ begin
   {$ifdef dbgScroll}DebugLn('doMouseWheelUP END');{$endif}
 end;
 
+function TCustomGrid.DoMouseWheelLeft(Shift: TShiftState; MousePos: TPoint
+  ): Boolean;
+begin
+  {$ifdef dbgScroll}DebugLn('doMouseWheelLEFT INIT');{$endif}
+  Result:=inherited DoMouseWheelLeft(Shift, MousePos);
+  if not Result then begin
+    GridMouseWheel([ssCtrl], -1);
+    Result := True; // handled, no further scrolling by the widgetset
+  end;
+  {$ifdef dbgScroll}DebugLn('doMouseWheelLEFT END');{$endif}
+end;
+
+function TCustomGrid.DoMouseWheelRight(Shift: TShiftState; MousePos: TPoint
+  ): Boolean;
+begin
+  {$ifdef dbgScroll}DebugLn('doMouseWheelRIGHT INIT');{$endif}
+  Result:=inherited DoMouseWheelRight(Shift, MousePos);
+  if not Result then begin
+    GridMouseWheel([ssCtrl], 1);
+    Result := True; // handled, no further scrolling by the widgetset
+  end;
+  {$ifdef dbgScroll}DebugLn('doMouseWheelRIGHT END');{$endif}
+end;
+
 procedure TCustomGrid.DoOnChangeBounds;
 var
   OldTopLeft: TPoint;
diff --git a/lcl/include/treeview.inc b/lcl/include/treeview.inc
index b82b6b586d..9143cf25b9 100644
--- a/lcl/include/treeview.inc
+++ b/lcl/include/treeview.inc
@@ -4698,6 +4698,23 @@ begin
   UpdateTooltip(MousePos.X, MousePos.Y);
 end;
 
+function TCustomTreeView.DoMouseWheelHorz(Shift: TShiftState;
+  WheelDelta: Integer; MousePos: TPoint): Boolean;
+var
+  NDelta: integer;
+const
+  cScrollStep = 50;
+begin
+  Result:=inherited DoMouseWheelHorz(Shift, WheelDelta, MousePos);
+  if not Result then
+  begin
+    NDelta := (WheelDelta * cScrollStep) div 120;
+    ScrolledLeft := ScrolledLeft + NDelta;
+    Result := true;
+  end;
+  UpdateTooltip(MousePos.X, MousePos.Y);
+end;
+
 function TCustomTreeView.DoDragMsg(ADragMessage: TDragMessage; APosition: TPoint; ADragObject: TDragObject; ATarget: TControl; ADocking: Boolean):LRESULT;
 begin
   Result:=inherited;