In 1999, the Minnesota state legislature amended the definition of child neglect to include a child s exposure to family violence. What was seen initially as a simple change brought about great turmoil in Minnesota's child protective services. This article reconstructs how this legislative change occurred, what resulted from the changed neglect definition, and what lessons may be drawn from Minnesota's difficult experience. The Minnesota legislature's actions must be placed in the context of a larger national examination of children's exposure to adult domestic violence that was underway in 1999 and continues today (see Weithorn, 2001). The National Council of Juvenile and Family Court Judges (NCJFCJ), along with the federal government and private foundations, had undertaken a national effort to improve the response of the courts, domestic violence programs, and child welfare agencies to families in which both adult domestic violence and child maltreatment or exposure to violence were occurring (NCJFCJ, 1998, 1999). In a related effort, the National Association of Public Child Welfare Administrators (2003) published national guidelines for responding to children exposed to domestic violence. Furthermore, the National Conference of State Legislatures had widely distributed a number of magazine articles, briefs, and a book that addressed this issue to state legislators (see Walton, 2003a, 2003b). These national organizations undertook this work in part as a result of a growing body of research revealing that almost half of the families in which child maltreatment occurs also show evidence of domestic violence (Appel & Holden, 1998; Edleson, 1999b; McGuigan & Pratt, 2001; O'Leary, Slep, & O'Leary, 2000) and that children exposed to adult domestic violence may experience subsequent negative developmental outcomes (Edleson, 1999a; Fantuzzo & Mohr, 1999; Margolin, 1998; Onyskiw, 2003; Rossman, 2001). The concern raised by all of these efforts generated great interest among policymakers and program planners across the country and resulted in a number of federally and privately funded demonstration projects (see http:// www.thegreenbook.info).