• Recent advances in psychiatric research methodology promise major progress. Simultaneously, however, mounting concerns about ethics of human experimentation have resulted in increased scrutiny and regulation that threaten scientific productivity. Virtually no systematic data have been gathered about the effects of research participation on treatment outcome or patient satisfaction. In this study 56 hospitalized depressed patients, who had agreed to participate in psychobiological research protocols, were then randomly assigned to treatment on a research unit or on standard adult inpatient (nonresearch) units. Research participants received more diagnosis-related somatic treatments, had a longer mean length of stay, and experienced trends toward greater symptom reduction and better consumer satisfaction. We conclude that research participation may be helpful to patients but that more systematic study is needed to help to resolve ethical questions and to assist risk-benefit evaluations.