Many countries, the local nomenclature for a veterinarian is a regulated and protected term, meaning that members of the public without the prerequisite qualifications and/or licensure are not able to use the title. This title is selective in order to produce the most knowledgeable veterinarians that pass these qualifications. In many cases, the activities that may be undertaken by a veterinarian (such as treatment of illness or surgery in animals) are restricted only to those professionals who are registered as a veterinarian. For instance, in the United Kingdom, as in other jurisdictions, animal treatment may only be performed by registered veterinary physicians (with a few designated exceptions, such as paraveterinary workers), and it is illegal for any person who is not registered to call themselves a veterinarian, prescribe any drugs, or perform treatment.

Most veterinary physicians work in clinical settings, treating animals directly. These veterinarians may be involved in a general practice, treating animals of all types; they may be specialized in a specific group of animals such as companion animals, livestock, zoo animals or equines; or may specialize in a narrow medical discipline such as surgery, dermatology or internal medicine . As with other healthcare professionals, veterinarians face ethical decisions about the care of their patients. Current debates within the profession include the ethics of certain procedures believed to be purely cosmetic or unnecessary for behavioral issues, such as declawing of cats, docking of tails, cropping of ears and debarking on dogs. The majority of veterinarians are employed in private practice treating animals (75% of vets in the United States, according to the American Veterinary Medical Association). mall animal veterinarians typically work in veterinary clinics, veterinary hospitals, or both. Large animal veterinarians often spend more time travelling to see their patients at the primary facilities which house them, such as zoos or farms. Other employers include charities treating animals, colleges of veterinary medicine, research laboratories, animal food companies, and pharmaceutical companies. In many countries, the government may also be a major employer of veterinarians, such as the United States Department of Agriculture or the Animal and Plant Health Agency in the United Kingdom. State and local governments also employ veterinarians.

Veterinary specialists are in the minority compared to general practice veterinarians, and tend to be based at points of referral, such as veterinary schools or larger animal hospitals. Unlike human medicine, veterinary specialties often combine both the surgical and medical aspects of a biological system. Veterinary specialties are accredited in North America by the AVMA through the American Board of Veterinary Specialties, in Europe by the European Board of Veterinary Specialisation and in Australasia by the Australasian Veterinary Boards Council. While some veterinarians may have areas of interest outside of recognized specialties, they are not legally specialists. pecialties can cover general topics such as anesthesiology, dentistry, and surgery, as well as organ system focus such as cardiology or dermatology. A full list can be seen at veterinary specialties.

Degrees in veterinary medicine culminate in the award of a veterinary science degree, although the title varies by region. For instance, in North America, graduates will receive a Doctor of Veterinary Medicine (Doctor of Veterinary Medicine or Veterinariae Medicinae Doctoris; DVM or VMD), whereas in the United Kingdom, Australia, New Zealand or India they would be awarded a Bachelor of Veterinary Science, Surgery or Medicine (BVS, BVSc, BVetMed or BVMS), and in Ireland graduates receive a Medicinae Veterinariae Baccalaureus (MVB). In continental Europe, the degree of Doctor Medicinae Veterinariae (DMV, DrMedVet, Dr. med. vet., MVDr.) or Doctor Veterinariae Medicinae (DVM, DrVetMed, Dr. vet. med.) is granted. Preveterinary courses should emphasize the sciences. Most veterinary schools typically require applicants to have taken one year equivalent classes in organic, inorganic chemistry, physics, general biology; and one semester of vertebrate embryology and biochemistry. Usually, the minimal mathematics requirement is college level calculus. Individual schools might require introduction to animal science, livestock judging, animal nutrition, cell biology, and genetics. However, due to the limited availability of these courses, many schools have removed these requirements to widen the pool of possible applicants.

Some veterinarians pursue post-graduate training and enter research careers and have contributed to advances in many human and veterinary medical fields, including pharmacology and epidemiology. Research veterinarians were the first to isolate oncoviruses, Salmonella species, Brucella species, and various other pathogenic agents. Veterinarians were in the forefront in the effort to suppress malaria and yellow fever in the United States. Veterinarians identified the botulism disease-causing agent, developed a widely used anesthetic induction drug produced an anticoagulant used to treat human heart disease, and developed surgical techniques for humans, such as hip-joint replacement, limb and organ transplants.