This enumeration specifies the drawing style for button-like classes, including group boxes, checkboxes, etc. The Flat , Popup , and Standard styles are fairly self-explanatory. The System style causes the repaint to be handled by the OS rather than the framework. You should set the System style if you wish to support Windows XP Themes on these objects, but bear in mind that you will then lose the framework features such as font and image support. public enum FlatStyle { Flat = 0 , Popup = 1 , Standard = 2 , System = 3 } HierarchySystem.Object System.ValueType System.Enum(System.IComparabl, System.IFormattable , System.IConvertible) FlatStyle Returned ByButtonBase.FlatStyle , GroupBox.FlatStyle , Label.FlatStyle Passed ToButtonBase.FlatStyle , GroupBox.FlatStyle , Label.FlatStyle |