The construction and development of theory is one of the central routes to scientific progress. But what exactly constitutes a good theory? What is it that people might expect from an ideal theory? This article advances a new model, which delineates truth, abstraction, progress, and applicability as standards (TAPAS) for a good theory. After providing the rationale for TAPAS, this article evaluates several social-psychological theories in terms of TAPAS, especially classic theories, and illustrates its utility with some more recent theoretical contributions of social psychology. This article concludes by outlining recommendations for effective theory construction and development, such as the utility of meta-analytic approaches for pursuing truth, the utility of theory-oriented courses and journals for pursuing abstraction, and the utility of adversarial collaboration for pursuing progress, and reaching out to major personal or societal issues for pursuing applicability. © 2013 by the Society for Personality and Social Psychology, Inc.