Basic Information:
Size:  Small.
Height:  Males - 10 inches at the withers, Females - 9.5 inches at the withers.
Weight: Males - 14 pounds, Females - 13 pounds.
Coat: Medium-long.
Color: Any color except white.
Energy: Medium.
Activities: Hunting, Earthdog Trials, Tracking, Agility, Obedience, Conformation.

Overview:
The bright-eyed, up-for-anything Cairn Terrier was bred in Scotland to dig into piles of rocks - the cairns from which he gets his name - in search of vermin. Today he's a full-time family pet and companion, but he's no lap dog. With his head up, ears, and tail twitching, he's always game for a long walk, wrestling with the kids, or ridding the backyard of invading squirrels.

The shaggy-coated Cairn only weighs 13 or 14 pounds, but he's a little dog who has no idea just how small he is. He's intelligent and fairly easy to train, with a streak of what some would call independence, but you might call stubbornness.
Cairn Terriers are very affectionate, particularly with children, and while some small dogs can't handle the rough-and-tumble games kids play, the Cairn Terrier loves them. He'll even invent some of his own. 

That's not to say every Cairn Terrier will automatically be great with children. Adult supervision of playtime along with training and socializing of the dog is still required. But in most cases, kids and Cairns are a match made in heaven.

Personality:
The Cairn might be small, but he's so confident that it's easy to forget his size. He has the typical Terrier independence and no-nonsense attitude, but he's a friendly dog who can adapt to any type of home -- from a city apartment to a country farm (both will allow him to practice his ratting skills). Alert, active, and curious, the Cairn functions as a watchdog, child playmate, and all-around family friend. 

When both dog and child have proper supervision and training, Cairns and kids fit together perfectly. Cairns are sturdy and forgiving of accidental bops on the head or stepped-on paws. Still, it's important to protect them from a toddler who doesn't yet understand how to pet a dog nicely. 

Don't expect the Cairn to be a lap dog, despite his small size. He might give you a minute or two of his time, but he's got things to do and places to go. Just be sure they don't involve digging up your garden: his large feet and strong nails not to mention his terrier instincts fit this pursuit perfectly. 

The Cairn is smart and learns quickly. There's never any need to yell at him or treat him forcefully; he'll respond to positive reinforcement in the form of praise, play, and treats as long as he knows you're in charge. Be firm and consistent in what you ask of him, and he'll be happy to play follower to your leader. Let him get the idea that you're wishy-washy, though, and this fearless and tenacious little dog will take it upon himself to run your household.

And without training, supervision, or appropriate levels of play, he'll become bored, spending his time chewing, barking, and digging to keep himself occupied. Don't let that happen! Challenge his brain he has a great one with puzzle toys and training sessions that are interesting and ever-changing, and keep him active every day with interesting walks or hikes (he is built for scrambling over rocks, after all) and fun playtimes. On wet or snowy days, let him chase a ball indoors or teach him to play hide and seek.

Health:
 All dogs have the potential to develop genetic health problems, just as all people have the potential to inherit the disease. Run from any breeder who does not offer a health guarantee on puppies, who tells you that the breed has no known problems, or who keeps puppies isolated from the main part of the household for health reasons. A reputable breeder will be honest and open about health problems in the breed and the frequency with which they occur in her lines. 

Cairn Terriers are fairly healthy, but they can be affected by certain genetic health problems. For one, Cairns can suffer from an enzyme deficiency that leads to nerve cell death known as globoid cell leukodystrophy, or lysosomal storage disease. A genetic test is available to identify carriers of this disease.

Many small dog breeds, including the Cairn, suffer from Legg-Calve-Perthes disease (LCPD), a bone disorder that requires surgery, as well as portosystemic shunts, a liver defect that usually requires surgical correction. There are no screening tests for these conditions. 

Other conditions that affect the Cairn Terrier (and lack screening tests) include craniomandibular osteopathy, allergies, and diabetes. Your puppy's breeder should be willing eager to go over the health histories of his parents and their close relatives and discuss how prevalent those particular health concerns are in his lines.