OBJECTIVE: To summarize the current status of behavioral research and practice in diabetes and to identify promising future directions. RESEARCH DESIGN AND METHODS: We review behavioral science contributions to diabetes in self-management and patient empowerment, interventions with children and adolescents, and special problems including blood glucose awareness training and complications such as depression. We also identify emerging areas in which behavioral science stands to make significant contributions, including quality of life, worksite and community programs, interventions using new information technologies, and translation research evaluating practical programs in representative settings. We then discuss the gap between the generally encouraging research on behavioral contributions to diabetes and the infrequent incorporation of such contributions in practice. Suggestions are made for how to close this gap, including ways to increase understanding of behavioral issues, opportunities for funding of key research and implementation questions, and how behavioral science principles can become more integrated into diabetes organizations and care. CONCLUSIONS: Changes are required on the part of behavioral scientists in how they organize and present their research and on the part of potential users of this knowledge, including other health professions, organizations, and funding agencies. Integrating behavioral science advances with other promising genetic, medical, nutritional, technology, health care, and policy opportunities promises not only to broaden our understanding of diabetes but also to improve patient care, quality of life, and public health for persons with diabetes.