Recent trends toward managed care in mental health settings require investigation of the efficacy and cost-effectiveness of treatments conducted over shorter time frames or with less therapist involvement. Findings are presented in an uncontrolled trial of two types of group behavioral treatments of OCD: group (GBT) and multifamily (MFBT). Seventeen patients (10 women and 7 men) diagnosed with OCD received a partially manualized GBT delivered by co-therapy teams in three groups of ten 2-hr sessions. Mean interview-based YBOCS scores reduced significantly at posttest and at 1-year follow-up, as did measures of overall functioning on the Sheehan Disability Scale at posttest and follow-up. A second cohort of 19 patients (14 women and 5 men) was treated with MFBT that included spouses/partners and parents in three co-therapy groups. Two groups received ten 2-hr sessions and one received twelve 2-hr sessions. YBOCS scores reduced significantly at posttest and at 1-year follow-up, with corresponding gains in disability scores. Both group treatments showed large effects comparable to those reported for a more intensive individual behavioral treatment. Comparisons of treatments indicated that similar proportions of subjects were reliably changed at posttest and follow-up respectively, but more MFBT than GBT participants were clinically significantly improved. These promising cost effective group treatments remain to be tested in a controlled trial.