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.
In the US, the majority of fellowships are accredited by the Accreditation Council for Graduate Medical Education ("ACGME"). There are a few programs that are not accredited, yet are actually well received, given the importance of being a Board Certified Physician in a primary specialty, where a Fellowship is often more based on research productivity.
The following are organized based on specialty required for the fellowship.
Adolescent Medicine
Allergy/Immunology
Cardiology
Child abuse (pediatrics only)
Critical care medicine
Emergency medicine
Endocrinology
Gastroenterology
Hematology
Infectious diseases
Neonatology (pediatrics only)
Nephrology
Oncology
Pulmonology
Rheumatology
Complex General Surgical Oncology
Hand Surgery
Pediatric Surgery
Trauma, Burns, and Surgical Critical Care
Vascular Surgery
Colon and Rectal Surgery
Thoracic Surgery
Hospice and palliative medicine
Plastic and Reconstructive Surgery
Non-ACGME Accredited Fellowships:
Abdominal Transplant Surgery
Hepatopancreatobiliary Surgery
Advanced Gastrointestinal, Minimally Invasive, Foregut, and Bariatric Surgery
Breast Surgery
Endocrine Surgery
Vascular Neurology
Endovascular Surgical Neuroradiology (Interventional Neurology, or Neurointerventional Radiology [NIR])
Neurocritical Care
Clinical Neurophysiology
Movement Disorder
Dementia/Behavioral Neurology
Neuroimmunology
Neuro-oncology
Neuro-ophthalmology
Geriatric Neurology
Headache Medicine
Sleep Medicine
Epilepsy
Neurohospitalist
Neurorehabilitation
Sports Neurology
Gynecologic Oncology
Maternal Fetal Medicine
Female Pelvic Medicine and Reconstructive Surgery
Reproductive Endocrinology
Minimally Invasive Gynecologic Surgery1
Pediatric and Adolescent Gynecology1
1 Not officially recognized as a subspecialty by the American Board of Obstetrics/Gynecology or the American College of Obstetrics/Gynecologists.