The Cadlab Work Station Design Environment is an integrated CAD environment. Like other integrated CAD environments, it consists of a single design management sub-environment and a set of application sub-environments integrated into a CAD framework. Unlike other integrated CAD environments, all of the components which combine to form the Cadlab Design Environment and the methodologies which are used to work with it are defined using a single object-oriented approach. By using an object-oriented approach, rapid integration, extension, and modification of the component sub-environments is possible. In this paper, the object-oriented Cadlab Design Environment is presented and the integration methodology is explained.