uses 
  ShellApi; 

procedure RenameDir(DirFrom, DirTo: string); 
var 
  shellinfo: TSHFileOpStruct; 
begin 
  with shellinfo do 
  begin 
    Wnd    := 0; 
    wFunc  := FO_RENAME; 
    pFrom  := PChar(DirFrom); 
    pTo    := PChar(DirTo); 
    fFlags := FOF_FILESONLY or FOF_ALLOWUNDO or 
              FOF_SILENT or FOF_NOCONFIRMATION; 
  end; 
  SHFileOperation(shellinfo); 
end; 


procedure TForm1.Button1Click(Sender: TObject); 
begin 
  RenameDir('C:\Dir1', 'C:\Dir2'); 
end;