My friend Mike's wife, Cathy, sent out a link to a Phoenix news story on a boy with Type I diabetes whose school is raising money to train him a diabetic alert dog from a Wildrose pup. Oddly enough, some of the best service dogs are also the best hunting dogs and vice versa. When I went in for my first dog/handler interview with Jill from ADW, she asked what sort of line my dog Danger was from. When I told her he was from a hunting line, she was quick to clarify: Hunting or field trialing?

The distinction is as important to service dog trainers as it is to hunting dog trainers. Labs have only been around as a breed—used primarily for waterfowl retrieving and hauling fishing nets—for about 130 years. Service dog programs weren’t formalized until the 1990 passage of the Americans With Disabilities Act (though they’d been used before that). Most service dogs are trained out of hunting litters for the simple reason that the desired characteristics are the same: Calmness, temperment, intelligence, a good nose, and loyalty to the handler.

But in the last 50 years or so, breeding goals have diverged. In the U.K, breeders prefer a slightly smaller (maybe 65 pounds) animal and value calmness and temperment above raw athletic power and retrieving drive. Maybe it’s the old British stereotype, but they just prefer a dog that’s more civil. These dogs, whether imported directly from the U.K. as Mike’s Wildrose stock is, or bred for those characteristics here, are known as British or U.K. Labs.

American field trialing dogs are selected more like thoroughbred race horses. Breeders look for strength, speed, retrieving drive, and huge water entries. These 90-plus-pound dogs are the ones you see at the Teva Mountain Games flying 25 feet off the end of the dock or lining 300 yards for a duck they can’t see. They’re something to watch, but they’re hardwired for that explosive energy. Don’t expect a field trial dog to sleep by your chair while you read a book.

Show dogs: Would it be impolite to call them dumb, overbred, more prone to hereditary diseases, and otherwise a terrible waste of working dog genetics? I’ve never understood why working dog breeds end up in dog shows. It’s like having a beauty pageant for longshoremen. More astounding is that the Westminster Kennel Club was started by a pair of gun dog enthusiasts.

So the first question you have to ask yourself when you go to get a dog is, What do I want? In a lot of cases, you can find a dog that meets your needs at an animal shelter. In others, you’ll want to go to a breeder. But just know that there’s a lot of variation even within breeds.

This article originally appeared on Outside K9, the former dog blog of Outside magazine, on April 25, 2009.