Anesthesiologists are the most extensively-trained anesthesia providers in the United States. Anesthesiologists are physicians (MD or DO) who have chosen to specialize in anesthesiology. Anesthesiologists in the United States must have completed an undergraduate college degree, including pre-medical requirements. Like other physicians, anesthesiologists complete four years of medical school. Physician training programs in the United States, without exception, require four years of residency training for board certification eligibility in the specialty of anesthesiology. An anesthesiology residency requires a one year medical or surgical internship followed by three years of anesthesiology training.

Anesthesiology residency training in the U.S. encompasses the full scope of perioperative medicine, including pre-operative medical evaluation, management of pre-existing disease in the surgical patient, intraoperative life support, intraoperative pain control, post-operative recovery, intensive care medicine, and chronic and acute pain management. After residency, many anesthesiologists complete an additional fellowship year of subspecialty training in areas such as pain management, cardiothoracic anesthesiology, pediatric anesthesiology, neuro anesthesiology, obstetric anesthesiology or critical care medicine.

The majority of Anesthesiologists in the United States are board-certified by a specialty medical board; either the American Board of Anesthesiology (ABA) or the American Osteopathic Board of Anesthesiology (AOBA). The ABA is a member of the American Board of Medical Specialties, while the AOBA falls under the auspices of the American Osteopathic Association.  Both Boards are recognized by the major insurance underwriters in the U.S. as well as by all branches of the U.S. Uniformed Services. Board certification by the ABA involves both a written and an oral examination. AOBA certification requires the same exams, in addition to a practical examination with examining physicians observing the applicant actually administering anesthetics in the O.R.
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