One of the mechanisms that are implemented in the cost containment movement in the health care sectors in western countries is the definition, by the third-party payer, of a set of preferred providers. The insured patients have different access rules to such providers when ill. The rules specify the copayments patients must pay when using an out-of-plan care provider. This paper studies the competitive process among providers in terms of both prices and qualities. Competition is influenced by the status of providers as in-plan or out-of-plan care providers. Also, there is a moral hazard of provider choice related to the trade-off between freedom to choose and the need to hold down costs. It is possible to achieve the first-best allocation by an appropriate definition of the reimbursement scheme when decisions on prices and qualities are taken simultaneously (as in primary health care sectors). In contrast, some type of regulation is needed to achieve the optimal solution when decisions are sequential (as in specialized health care sectors). We also derive normative conclusions on how price controls should be implemented in some European Union member states.