Treatment outcome was evaluated for perinatal cocaine addicts admitted to a hospitalbased day treatment clinic, organized as a modified therapeutic community (TC) modality. The perinatal program consisted of a specialized track for women embedded within this larger coed day treatment clinic. A total of 87 perinatal women (28 pregnant at intake, the remaining 59 postpartum) were compared with cohorts of nonperinatal women (N= 63) and men (N= 158) admitted during the period of evaluation (September 1989 through December 1993).In logistic regression analysis, successful discharge urine status (last three urines prior to discharge drug-free) was associated with current child custody involvement (odds ratio = 2.80, 95% C.I. = 1.16–6.72), entering treatment when not postpartum (odds ratio = 0.15, 95% C.I. = 0.05–0.42), and taking psychiatric medication (odds ratio = 2.04, 95% C.I. = 1.11–3.72). Both pregnant and postpartum perinatal women showed a similar pattern of shorter treatment as compared with nonperinatal women and male clients, averaging 2 months of treatment as compared with 4 months for nonperinatal clients. Factoring out pregnancy and postpartum status, the women in treatment fared as well as men with respect to both retention and discharge urine standings. This finding indicates that programmatic modifications need to address specific perinatal issues and not gender issues per se. Also, a differential pattern in discharge urine status of women who enter treatment while pregnant vs. those who enter when postpartum suggests that outreach and recruitment be targeted, but not limited, to pregnant women.