The extensive changes in mental health services over the past 25 years negate the possibility of an overall research summary. Instead, we identify six pivotal topics to explore in depth: (1) the paradigm shift to a biopsychosocial mental illness etiology, (2) the organization and financing of mental health care, (3) community-based programs for adults with serious mental illness, (4) the role of families and consumers, (5) services for children and adolescents with serious emotional or mental disturbances, and (6) the interface with criminal justice. The article concludes with a discussion of future issues in mental health services research and the role of social work researchers.