Evaluation of physicians in the credentialing processes of hospitals has generally been viewed as focused upon whether the physicians will provide services to patients at the appropriate level of professional performance and will not engage in disruptive behavior at the institution. Three measures--exclusive contracting, medical staff planning, and exclusive credentialing--have been employed, singly or in combination, at many hospitals to restrict or to deny medical staff appointments and clinical privileges to professionally qualified and competent physicians. Because the hospitals have articulated links, when employing these restrictive measures in making credentialing decisions, to the public's interest in their being able to provide good quality services to the communities they serve, the hospitals have usually been successful in litigation brought by physicians who have been denied staff appointment or specific clinical privileges.