Many canine health problems can be prevented with a good healthy diet, an appropriate environment with plenty of exercise, and routine veterinary care. Regardless of the dog's age and apparent health, a veterinarian should see all dogs at least once per year. A trained veterinarian can detect problems that most people cannot, and once the dog is showing symptoms it may be too late to do anything about the problem.
Vaccines
There are two common vaccines that most dogs should be given: Distemper and Rabies. The Distemper vaccine is usually a combination vaccine that may include: distempter, adenovirus, leptospira canicola, parainfluenza, and parvovirus. Puppies are usually given a series of 2-4 vaccines to properly boost the immune response but it depends on their age and sometimes breed. Your own veterinarian will come up with a vaccination plan that is right for you and your dog.
The initial Rabies vaccine can be given at 12 weeks of age and is good for one year. Rabies boosters are good for 1-3 years, depending on the laws of the local municipality.
There are other vaccinations to discuss with your veterinarian that may or may not be required or recommended based on you and your dog's activities and lifestyle.