Using MEDLINE and other Internet sources, the authors perform a systematic review of published literature. A total of 109 articles and reports are identified and reviewed that address the development, implementation, outcomes, and trends related to Managed behavioral health care (MBHC). MBHC remains a work in progress. States have implemented their MBHC programs in a number of ways, making interstate comparisons challenging. While managed behavioral health care can lower costs and increase access, ongoing concerns about MBHC include potential incentives to under-treat those with more severe conditions due to the nature of risk-based contracting, the tendency to focus on acute care, difficulties assuring quality and outcomes consistently across regions, and a potential cost-shift to other public agencies or systems. Success factors for MBHC programs appear to include stakeholder involvement in program and policy development, effective contract development and management, and rate adequacy.