A primary care physician is a physician who provided both first contact for a person with an undiagnosed health concern as well as continuing care of varied medical conditions, not limited by cause, organ system, or diagnosis. A primary care provider (PCP) is a health care practitioner who sees people that have common medical problems. This person is most often a doctor. However, a PCP may be a physician assistant or a nurse practitioner. Your PCP is often involved in your care for a long time.