In 2002, a large percentage of preschool children with employed mothers were in full-time care each week. Forty-two percent of children under age 5 with employed mothers spent at least 35 hours a week in child care. The proportion is even greater (50.6 percent) among children whose mothers worked full-time. These findings reinforce the important role that child care plays in the lives of America's youngest children and the need for policymakers to pay close attention to the quality of that care.