Although puppies are a barrel of fun and cute as the dickens, remember the wise old saying, "Age before beauty." Just because an adult dog is no longer young doesn't mean he doesn't have a world of things to offer you. Folks sometimes have the mistaken notion that if you don't raise a dog from scratch, you'll only have trouble. Nothing could be further from the truth. Sure, it may be easier in some ways for a tiny pup to bond with you, but there are definite advantages to the older dog. For one thing, they've settled down from puppyhood and might even have had some training already. If you've never had a puppy, you might not realize just how much energy he has. Keeping up with a puppy can be exhausting -- and you can't turn him off or send him to his room to play if you've had a hard day.
Look for the same clues for health problems as with a puppy, and ask the source of the dog if your veterinarian can examine the dog before you adopt him. If you're adopting directly from the previous owner, ask to see the dog's health records so you can check on illnesses, vaccination history, and spaying or neutering (older dogs have probably already been "fixed," which is a bonus).
Far more so than with a puppy, an adult dog is a "what you see is what you get" proposition. Most all pups are cute, cuddly, and passive, but some will grow up and stay that way, and others will grow up to be the canine equivalent of Jesse James. An adult dog's personality is pretty much set, giving you a better handle on how well he'll fit into your household and whether or not he'll get along with any other pets. Since he's got all his adult teeth and is past the energetic phase of frantic puppy activity, a full-grown dog is less likely to do wholesale destruction and his longer attention span makes him easier to train.
If you have your heart set on a purebred, opting for an older dog may be easier than you think. There are a large number of breed rescue clubs that specialize in placing dogs of their particular breed who have been found as strays, taken from unsafe situations, or simply retired from the showing or the racetrack. Adopting a rescued stray, a retired show dog, or racing Greyhound will give you all the joys and benefits of dog ownership...and do a great favor for the dog, too. Check the classified ads in newspapers under the breed in which you are interested, contact breeders (they advertise in dog magazines), or call your local humane society for more details.
One last thought about the "secondhand" dog: A dog of any age can be trained and will adapt to -- and be a loving, loyal companion for -- a new family. You really can teach an old dog new tricks!
When you have made up your mind between a puppy and an adult dog, you then need to decide whether you prefer a mixed-breed or purebred. We'll learn about purebred dogs in the next section.