A fellowship is the period of medical training, in the United States and Canada, that a physician, dentist, or veterinarian may undertake after completing a specialty training program (residency). During this time (usually more than one year), the physician is known as a fellow. Fellows are capable of acting as an attending physician or a consultant physician in the specialist field in which they were trained, such as internal medicine or pediatrics. After completing a fellowship in the relevant sub-specialty, the physician is permitted to practice without direct supervision by other physicians in that sub-specialty, such as cardiology or oncology.