{ When you want to control how much your users can resize your form, you can control that by setting the MinMax values. (If you use the resize method to limit the size, it will work, but it won't look quite as good.) Note: To make it so that the user cannot change the form's size at all, make the min and max sizes the same values. This is an example of how to declare and use the wm_GetMinMaxInfo windows message in your applications. } unit MinMax; interface uses SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls, Forms, Dialogs; type TForm1 = class(TForm) private { Private declarations } procedure WMGetMinMaxInfo(var MSG: Tmessage); message WM_GetMinMaxInfo; public { Public declarations } end; var Form1: TForm1; implementation {$R *.DFM} procedure TForm1.WMGetMinMaxInfo(var MSG: Tmessage); Begin inherited; with PMinMaxInfo(MSG.lparam)^ do begin with ptMinTrackSize do begin X := 300; Y := 150; end; with ptMaxTrackSize do begin X := 350; Y := 250; end; end; end; end.