How might policy makers, consumers, small employers, and others identify and overcome barriers to the growth of health care purchasing coalitions? Researchers at the Economic and Social Research Institute, with a subcontract to Mark Hall, J.D., investigated why the growth of such coalitions has not been greater, given that the literature portrays consensus among analysts that coalitions are of value in the purchasing of coverage. The researchers identified and analyzed legal and policy constraints, structural and technical features, and political factors that might have slowed the adoption of coalitions. Ultimately, the objective of the study was to further understanding of the barriers to coalitions and formulate policy recommendations providing incentives to achieve the benefits predicted to and from coalition purchasing.