This paper argues for a more extensive study of self-knowledge. From the cognitive perspective, self-knowedge is a critical component of personality. Until quite recently, however, the study of self-knowledge has been narrowly conceived, focusing primarily on how individuals describe their roles and characteristic behaviors. Yet individuals also have knowledge about their preferences and values, their goals and motives, and their rules and strategies for regulating behavior. These dynamic aspects of self-knowledge are significant because they can be importantly revealing of future behavior. The content and organization of self-knowledge is important first because it indicates which domains of behavior are regarded as the most self-relevant. It is in these domains that the strongest links between personality and behavior will be observed. Second, self-knowledge cognitively represents desired and undesired states for the self, as well as specific ideas about how to realize or avoid these states. It thus indicates the likely course of behavior in self-relevant domains. A number of recent research efforts can be intepreted as explorations of self-knowledge. These are briefly reviewed and integrated to provide a general outline for an expanded view of self-knowledge.