The past decade saw an explosive growth in psychological research on law (particularly the judicial process) that continues unabated. This article presents an intellectual history of this research and a critical assessment of its contemporary developments. It begins by tracing four stages in the relations between psychology and law that serve to place present scholarship in perspective. Then follow two sections consisting of conceptual, methodological, and jurisprudential critiques of two topics, respectively, that traditionally have been and still remain at the center of research attention: the pretrial phase of the criminal process (eyewitness identifications) and the criminal trial itself (jury selection, jury decision making, and presentations of evidence and law to the jury). Finally, some themes are culled from past and present experience that capture the mood, difficulties, and prospects of applying psychology to the law. The purpose of this theoretical overview of the field is to suggest some insights into two recurrent questions: why has psychological research not had more of an impact on the judicial process, and what can be done about it?