The authors describe the successful use of an adjunctive group psychotherapy for substance-abusing patients with major psychiatric disorders (bipolar, schizophrenia, schizoaffective, psychotic depression, and atypical psychosis). The group utilizes a psychoeducational approach that focuses on substance abuse causes and consequences, principles of recovery, and relapse prevention strategies. Eight patients with prolonged histories of abuse of cocaine, alcohol, marijuana, or other drugs were enrolled in this weekly group treatment at a community mental health center drug treatment program, while continuing in treatment with their current case manager or primary therapist. Six of the eight patients achieved periods of stable abstinence, documented by self-report, urine toxicology screens, continued group attendance, and improved social functioning. Case examples are utilized to illustrate the group process.