In this article a historical overview of the evolution of the Women's Trauma Integrated Services model at the Substance Abuse and Mental Health Services Administration (SAMHSA) is presented. Milestones in women's services policy development at SAMHSA (1992-1998) and in trauma treatment development for four different trauma populations (1960-1998) are discussed. SAMHSA's 5-year Women, Co-Occurring Disorders and Violence Study (1998-2003) is described, and the rationales for a number of basic decisions about the study design are presented. New knowledge application initiatives and plans at SAMHSA to further develop the Women's Trauma Integrated Services Model are outlined.