While it’s important to take your pet to your veterinarian when he’s sick, you also need to have him periodically checked out when he appears to be healthy. This is called a “wellness examination” or a check-up. Its purpose is not to treat existing symptoms, but to ensure no illnesses are in their early stages to maintain your pet’s good health. The frequency of wellness exams should be a decision you make after consulting with your veterinarian about your pet's current health. Very young and older pets may need to be seen more frequently than once a year.