Although the most common dogs at a shelters are mongrels, you can often find a certain breed, if your heart is set on one. But before you take home a purebred, it's prudent to learn about particular genetic traits the breed possesses. Hardly any terrier can resist chasing a squirrel, and many will pursue another dog too. Scent hounds, such as beagles and dachshunds, typically bark a lot because they were bred to alert hunters. Are you prepared for a retriever who begs you to throw a ball 50 times? If you want to scare burglars, a Doberman or a Rottweiler might do the trick, not because they are necessarily aggressive, but because most thieves think they are. They can, however, make friends and neighbours fearful as well.
Research the breed's medical issues to know what to watch out for - and the kinds of costs associated with those issues. Labradors are generally easygoing, but can jump up on people unless they're taught otherwise. Labs are also prone to hip problems. And bulldogs are at risk of getting "cherry eye," a glandular eye infection.
Small spaces don't necessarily mean that a small dog is your best choice. A tiny breed with a loud bark may not make the best roommate. Great Danes, however, can share a relatively small apartment because of their mellow temperament and low energy level.
Be prepared for adapting to your dog. "I had a truly wonderful Dalmatian for 13 years," says Trish McMillan of the ASPCA, "but I knew before I got her that these dogs were bred to run dozens of miles a day with a horse and carriage, to guard the stable from robbers and to control rodent life. I got a mountain bike to give her enough exercise, socialised her to people so she'd be friendly with strangers and was lucky in that she didn't have a huge amount of 'prey drive,' so she could coexist with cats and other small animals in harmony."