Vaccinations (immunizations, "shots") have saved the lives of millions of dogs. Before the days of effective vaccines, dogs routinely died from infectious diseases, like distemper and parvovirus, even from complications of upper airway infections. Current vaccination programs also protect our dogs (and us) from the threat of rabies.

Routine vaccinations are essential for prevention of infectious diseases in puppies. Puppies receive immunity against infectious disease in their mother's milk, called maternal antibodies. However, this protection begins to disappear between 6 and 20 weeks of age. To protect puppies during this critical time, a series of vaccines is given every 3-4 weeks until 16 to 20 weeks of age. The typical vaccine is a "combination" that protects against canine distemper virus, canine adenovirus, parainfluenza, and canine parvovirus (commonly abbreviated DHPP).

Some puppies will require a kennel cough vaccine (bordetella) if a trip to a kennel is likely. In some areas, leptospirosis may be incorporated into the vaccination series based on risk of exposure.