Medical care has become a team effort. Most of the laws dealing with responsibilities of physicians and nonphysician medical care providers [This term is used to denote physician’s assistants, nurse practitioners, child health associates, public health nurses, and other personnel with medical care training who participate in the medical care delivery team.] (NPPs) are out of touch with modern practice patterns. This is most evident in MCOs where NPPs are widely used with very diffuse supervision. Unlike private practice settings where there are a few NPPs reporting to a smaller number of physicians, NPPs in MCOs are often used in situations where they have no single physician who is responsible for their practice. This is a legal problem because in many situations the law, as embodied in the cases and statutes of each state, is at odds with the routine practice of medicine. The law presumes that all patients will have a single, identified treating physician who will control all aspects of the patient’s care, and who is the boss of all the nonphysician members of the medical care team. This is not the case in most MCO practice.