Because of their rapid growth, immature biologic systems, and their developmental characteristics, children are uniquely vulnerable to exposure to environmental hazards. One of these is lead. Revised lead screening guidelines, published by the Centers for Disease Control and Prevention in Fall 1997, no longer advocate universal screening in some places. These guidelines will (1) require new policies from local public health agencies, (2) require new approaches for clinicians and managed care organizations, especially those with Medicaid-recipient enrollees, to conduct screening of children who may be at risk for exposure to lead, (3) offer new challenges for environmental follow-up to children identified with elevated lead levels, and (4) provide opportunities for collaboration between managed care and public health agencies.