Key findings from the Women, Co-Occurring Disorders, and Violence Study (WCDVS) conducted in 1998 to address the lack of appropriate services for women with trauma histories include: (1) gender-specific services are critical in creating a healing environment; (2) the contributions of women who have experienced trauma in their lives can be an essential component of crafting effective services; (3) group environments are key to restoring trust and promoting healing; and (4) the most effective programs integrate trauma, mental health, and substance abuse services, rather than treating them separately. Millions of women suffer from co-occurring mental health and substance abuse disorders. Among them, a great many are also trauma survivors who have experienced violence and abuse. The WCDVS was a nationwide study of outcomes and costs associated with developing and implementing a comprehensive trauma-informed treatment program. The goal was to produce information and knowledge about an integrated services approach for women with co-occurring mental health and substance use disorders, who have histories of physical and/or sexual abuse. The study was a two phase study, totally 14 sites, conducted over 5 years, from 1998 to 2003. The study framework required all service interventions to be gender specific, culturally competent, trauma-informed and trauma specific, comprehensive, integrated, and involving consumer/survivor/recovering (C/S/R) women. Of the original 2,729 women enrolled in the study, 2,006 were interviewed to determine if their mental health, substance abuse and trauma symptoms had improved. Examples of intervention models, study sites and study implications are presented.