This paper discusses the types of knowledge associated with design objects, examines some of the representational needs of each type, and considers how they might be used for analogical reasoning. 1. KNOWLEDGE TYPES The purpose of design is to produce knowledge about a designed object which can then be used to manufacture that object. Obviously this knowledge is not produced from nothing, but is developed using some other, given knowledge. The knowledge associated with design objects is often classified into the following types: . Structural knowledge -- knowledge about the components which comprise the object and their relations; . Behavioral knowledge -- knowledge about the behavior of the object, i.e., about ways the device responds to changes in its environment and/or in its own state; . Teleological knowledge -- knowledge about the purpose and the way the object is intended to be used; . Functional knowledge -- knowledge about how the behavior of the object is used to a..