A specialist is a veterinarian who is board certified in a clinical specialty recognized by the American Veterinary Medical Association. To gain board Certification in a specialty, a doctor must complete three to four years of training following completion of veterinary school. Only board certified specialists are given the title of "Diplomate" in the college of their specialty. The AVMA currently recognizes 21 specialty boards or colleges.

The American College of Veterinary Surgeons and The American College of Veterinary Internal Medicine are specialty groups consisting of board certified doctors (diplomates) in the United States, Canada, Europe, Australia, and New Zealand. Approximately 25% of the diplomates are in private practice while the remainder are involved in university teaching and research. Specialty colleges cover the following specialties: dentistry, dermatology, emergency and critical care, internal medicine (neurology, oncology, and cardiology), ophthalmology, pathology, radiology and surgery.