Over the pase 20 years, a sizable body of literature has developed which serves to establish that stressful life events are associated with the onset, incidence, and prevalence of a wide range of physical and psychiatric disorders. As measured by the Holmes and Rahe Social Readjustment Rating Scale, or similar instruments, the stressful life events are fundamentally sociological in nature. Yet, paradoxically, the research has been largely limited in the relevant basic sociological theory and data brought to or yielded from investigation. Recently, however, several prominent researchers have emphasized the importance of studying the role of social support systems as possible buffers or mediators of stress. The most basic objective of this paper is to contribute to the advancement of such studies by clearly identifying key empirical, theoretical and methodological problems and suggesting some approaches to their resolution. Specifically, this paper offers: a) a selective review of the essential status of empirical knowledge; b) an examination of the nature and significance of social support systems; c) clarification of methodological and theoretical problems; and d) detailed proposals for approaching problems of measurement and research design.