This research brief describes the developmental risks present in a cohort of children coming into contact with the child welfare system between 1999 and 2000, as well as the services the children receive to address these risks. The findings are drawn from the National Survey of Child and Adolescent Well-Being (NSCAW), a unique study that provides detailed information about the well-being and experiences of children and families in the child welfare system. This research brief juxtaposes data on the developmental risks present in children who have been investigated by child protective services (CPS) with their levels of service receipt approximately 7 months after investigation (on average). The brief concentrates on the cognitive and socioemotional development of children and answers the following questions: (1) What proportion of children in this study show significant developmental delays in the areas of cognitive and socioemotional development? (2) Given the level of need, what percentage of children in the NSCAW is receiving mental health and special educational services?; (3) How do these levels of need and service receipt compare for preschool age and school age children? and (4) Are there differences in the needs and service receipt of children in in-home and out-of-home care? The NSCAW data indicate that both preschoolers and school age children in contact with the child welfare system show a variety of developmental risks. Many children involved with the child welfare system are not receiving needed services that will enhance their future development. Moreover, the findings suggest that child welfare agency staff need better tools for assessing children's developmental needs. This is the third in a series of NSCAW research briefs, developed by Caliber Associates from the Wave 1 CPS Report, focused on children coming into contact with the Child Welfare System. (Contains 3 figures.)