Multilevel modeling was used to assess the program characteristics associated with treatment retention among 637 women in 16 residential drug treatment programs in the Drug Abuse Treatment Outcome Study. Women who were pregnant or had dependent children had higher rates of retention in programs in which there were higher percentages of other such women. Longer retention was associated with higher rates of posttreatment abstinence. Bivariate analyses showed that programs with higher proportions of pregnant and parenting women provided more services related to women's needs. The findings support the provision of specialized services and programs for women in order to improve outcomes of drug abuse treatment.