Do medical patients with a high quantity or quality of social relationships have greater chances of recovery and survival than more isolated individuals? This article reviews longitudinal studies of social relationships and recovery published since the last major reviews of this field. Reports of 26 such projects were located, primarily in the areas of heart disease (13 studies) and breast cancer (7 studies). Being married (or socially supported in other ways) was generally associated with survival or freedom from recurrence in multiyear follow-up studies of myocardial infarction (MI) and coronary artery disease patients, although social support produced negative or mixed results in studies of short-term physical adaptation after Ml or bypass surgery. Studies relating marital status and other support variables to recurrence and survival in breast cancer patients also had mixed results. The small number of studies, and other limitations associated with them, suggest caution in drawing strong conclusions.