Health plans have incentives to discourage high-cost enrollees (such as persons with mental illness) from joining. Public policy to counter incentives created by adverse selection is difficult when managed care controls cost through methods that are largely beyond the grasp of direct regulation. In this article, the authors evaluate three approaches to dealing with selection incentives: risk adjustment, the carving out of benefits, and cost- or risk-sharing between the payer and the plan. Adverse selection is a serious problem in the context of managed care. Risk adjustment is not likely to help much, but carving out the benefit and cost-sharing are promising directions for policy.