The spacing effect refers to the advantage in memory for information repeated at separate points in time over information repeated in massed fashion. This phenomenon has been extensively studied in psychology and has a wide scope of application. In spite of its possible applications, particularly related to advertising effectiveness, the spacing effect and its underlying theories have received limited attention in marketing. Evidence suggests that encoding variability theory, the one most frequently cited in marketing to explain the spacing effect, cannot explain existing empirical evidence as well as two other theories, reconstruction theory and study-phase retrieval theory. This paper reviews these theories, as well as extant research, and discusses implications for advertising and directions for future research in marketing. © 2009 Wiley Periodicals, Inc.