Insight-oriented group psychotherapy is a common modality of treatment on inpatient psychiatric wards, yet its effectiveness for acutely hospitalized patients has not been adequately studied. A comparison was made of the effects of three experimental conditions (insight-oriented group psychotherapy, activity-oriented task group, and unstructured control condition) on 86 acutely hospitalized psychiatric patients at a United States Air Force teaching hospital. The group psychotherapy and task group patients did not show greater improvement after 20 days of hospitalization than control patients. In fact, significantly more psychotic patients scored worse in the group psychotherapy condition. It is suggested that insight-oriented group psychotherapy may not be an effective treatment modality during the first 3 weeks of psychiatric hospitalization, especially for psychotic patients.