Diabetes is a chronic illness that places a significant self-management burden on affected individuals and families. Given the importance of health behaviors—such as medication adherence, diet, physical activity, blood glucose self-monitoring—in achieving optimal glycemic control in diabetes, interventions designed and delivered by psychologists hold promise in assisting children, adolescents, and adults with diabetes in improving their health status and lowering their risk of serious complications. This article first provides an overview of diabetes self-management and associated challenges and burdens. Socioeconomic status factors that may influence diabetes management and outcomes are briefly highlighted. We then review the evidence base for select psychosocial factors that may be implicated in diabetes self-management. Modifiable targets of psychological intervention are presented across 3 overarching domains: (a) knowledge, beliefs, and related cognitive constructs; (b) emotional distress and well-being; and (c) behavioral skills and coping. Important methodological issues facing future research are discussed, along with opportunities for psychologists in improving the care and treatment outcomes of individuals and families living with diabetes. In conclusion, we advocate for continued research emphasis on improving psychosocial aspects of living with diabetes, with greater attention to the situational context in which the self-regulatory processes underlying self-management occur. Psychologists have important roles to play in reducing emotional distress, improving patient knowledge, and providing training in behavioral skills to promote successful self-management and to support patient-centered diabetes care.