Aspects of the present invention relate to a method of controlling the appearance of a graphical object in a graphical user interface. In an embodiment of an aspect of the invention, an object, such as a widget, in a graphical user interface comprises an instance of a widget class in which arr defined properties and/or methods which control operation of the object; and an associated instance of a look object class in which are defined properties and/or methods which control the look of the object.