Ethical concerns relating to managed care discussed in this essay include incentives to underutilize services, delays in care, postponement of consultation or hospitalization, gatekeeping, patient satisfaction, physician satisfaction, and information disclosure. Because managed care is here to stay, physicians and patients must learn to understand it and develop methods to work with it, preserving the overriding principle that the physician's first obligation is to be the patient's advocate. Physicians must continue to practice good medicine, eliminate that which is unnecessary, and be conscious of the need to contain costs.