The purpose of this chapter is to examine several epistemological questions underlying the nature of theory in the environment-behavior (EB) and design fields) Among these questions are: What is an EB theory, or, said differently, what are the necessary and sufficient conditions for something to be called a theory? What is the form and scope of different things that purport to be theories dealing with EB relations? What are the similarities and differences between EB theories and design theories, and is it possible to integrate theories linking environment, behavior, and design?2 lin their very influential chapter on world views, Altman and Rogoff (1987) refer to the discipline as "environmental psychology." The more general term "environment and behavior" encompasses environmental psychology, behavioral and social geography, environmental s0ciology, human factors, social and behavioral factors in architecture, and urban social planning. The range of theories discussed in this chapter will pertain not only to those in environmental psychology but also to those in the broader environment, behavior, and design field. 2These questions have been examined in a graduate seminar "Theories of Environment-Behavior Relations," which I offered between 1983 and 1997 at