Specialized substance abuse treatment programs have been developed for women within the past two decades. This article presents the results of a secondary analysis of a regional database of drug abuse treatment programs that compared the characteristics of women-only (WO) and mixed-gender (MG) programs across three treatment modalities. In general, WO programs differed from MG programs in their policies regarding fees, sources of payment, special populations served, services offered, and treatment capacity, process, and duration. The differences in program characteristics reflect broader societal gender differences, including women's generally lower economic status and primary responsibility for child-rearing.