Managed care organizations would appear to be natural advocates for, and users of, cost-effectiveness analysis (CEA) as a tool for maximizing health outcomes for their covered populations within fixed budgets. There is, however, little evidence that CEA plays a major role in managed care decision making. The purpose of this paper is to identify barriers to both conducting and using CEA in managed care decision making. Lack of understanding about the value and applicability of CEA, and incentives that do not align with a lifetime perspective on either health outcomes or costs may be at least as important as perceived or real methodological limitations of the methodology. Research focused on ways to overcome these barriers, and thereby improve resource allocations, is recommended.