Orient controls in dialog boxes in the direction people read. In countries where roman alphabets are used, this means left to right, top to bottom. Locate the primary field with which the user interacts as close to the upper left corner as possible. Follow similar guidelines for orienting controls within a group in the dialog box.
Lay out the major command buttons either stacked along the upper right border of the dialog box or lined up across the bottom of the dialog box. Position the most important button — typically the default command — as the first button in the set. If you use the OK and Cancel buttons, group them together. You can use other arrangements if there is a compelling reason, such as a natural mapping relationship. For example, it makes sense to place buttons labeled North, South, East, and West in a compass-like layout. Similarly, a command button that modifies or provides direct support for another control may be grouped or placed next to those controls. However, avoid making that button the default button because the user will expect the default button to be in the conventional location.