Veterinary medicine is defined as the application of medical, diagnostic, and therapeutic principles to companion, domestic, exotic, wildlife, and production animals.Veterinary Science is vital to the study and protection of animal production practices, herd health and monitoring spread of widespread disease.It requires the acquisition and application of scientific knowledge in multiple disciplines and applies technical skills towards disease prevention in both domestic and wild animals.Human health is protected by veterinary science working closely with many medical professionals by the careful monitoring of livestock health as well as its unique training in epidemiology and emerging zoonotic diseases worldwide.

Veterinary medicine is informally as old as the human/animal bond but in recent years has expanded exponentially because of the availability of advanced diagnostic and therapeutic techniques for most species.Animals nowadays often receive advanced medical, dental, and surgical care including insulin injections, root canals, hip replacements, cataract extractions, and pacemakers.Veterinarians assist in ensuring the quality, quantity, and security of food supplies by working to maintain the health of livestock and inspecting the meat itself.Veterinary scientists are very important in chemical, biological, and pharmacological research.Veterinarians treat disease, disorder or injury in animals, which includes diagnosis, treatment and aftercare. The scope of practice, experience and specialty of the individual veterinarian will dictate exactly what interventions they perform, but most will perform surgery (of differing complexity).

Unlike in human medicine, veterinarians must rely primarily on clinical signs, as animals are unable to vocalize symptoms as a human would. In some cases, owners may be able to provide a medical history and the veterinarian can combine this information along with observations, and the results of pertinent diagnostic tests such as radiography,CT scans, MRI, blood tests,urinalysisand others.Veterinarians must consider the appropriateness of euthanasia("putting to sleep") if a condition is likely to leave the animal with a poor quality of life or  in pain , or if treatment of a condition is likely to cause more harm to the patient than good, or if the patient is unlikely to survive any treatment regimen. Additionally, there are scenarios where euthanasia is considered due to the constrains of the client's finances.

As with human medicine, much veterinary work is concerned with prophylactic treatment, in order to prevent problems occurring in the future. Common interventions are vaccinationagainst common animal illnesses, such as distemperor rabies, and dental prophylaxis to prevent or inhibit dental disease. This may also involve owner education so as to avoid future medical or behavioral issues.Additionally veterinarians have important roles in public health and the prevention of zoonoses