According to the American College of Nurse Practitioners, "A nurse practitioner (NP) is a registered nurse with advanced academic and clinical experience, which enables him or her to diagnose and manage most common and many chronic illnesses, either independently or as part of a health care team. A nurse practitioner provides some care previously offered only by physicians and in most states has the ability to prescribe medications. Working in collaboration with a physician, a nurse practitioner provides high-quality, cost-effective and individualized care for the life span of patient's special needs."