A formal evaluation process can help healthcare organizations assess the current and/or potential value of a group purchasing organization (GPO). Healthcare organizations should approach a GPO evaluation as if they were entering into a new relationship. The evaluation should include purchasing and financial services, value-added services, and corporate relations/business practices. Healthcare organizations should consider the potential economies of scale and other services offered by a GPO. Healthcare organizations should consider using acceptable substitutes for products currently used or seeking products through alternative sources if doing so achieves greater value.