Little is known about welfare reform's effects on family structure and children's living arrangements, an important focus for reformers. Using March CPS data, the authors find that state welfare waivers are associated with children being less likely to live with unmarried parents, more likely to live with married parents, and more likely to live with neither parent. Children living with neither parent are living with grandparents or other relatives, or rarely, in foster care. The estimates vary somewhat by children's race and ethnicity. Due to the limited variation in TANF's implementation timing across states, the authors focus on the waiver results.