Slightly bigger than some of their toy group counterparts, Shih Tzus remain one of the most popular companion breeds in the United States thanks to their affectionate and playful nature. The storied dogs originally served as palace pets during the Tang Dynasty.The Einstein of the toy group, papillons can compete at the top agility trials alongside bigger brainiacs like border collies and Shetland sheepdogs. They don't look too shabby either; papillons get their French name because of their delicate, butterfly-like ears.

Cavalier King Charles Spaniel:

Ever since Charlotte owned a Cavalier on Sex and the City, fans have flocked to this graceful, easily trained pup. As you would expect, they're well-suited for urban living. A brisk, daily walk will keep them happy and healthy.

Chihuahua:

A charming and outgoing pet, the Chihuahua is the stereotypical lap dog. But these canines can be a bit "sassy," i.e., somewhat temperamental and difficult to train.

Pomeranian:

Pomeranians are alert, bold, and curious — some may even call them nosy. Their excitable nature can lead to lots of playtime but again, their 3- to 7-pound stature makes them a little too delicate for overeager kids.

Yorkshire Terrier:

Spunky and independent, Yorkies are often indifferent to their small size. They're usually affectionate and determined, and like their name suggests, terriers by nature. The breed got its start as ratters in English clothing mills.

Brussels Griffon:

This terrier-like companion recently skyrocketed into the limelight after Newton the Brussels Griffon won the most recent National Dog Show (and drew comparison to ewoks). Alert and loyal, this is exactly the kind of sidekick you'd want on a Star Wars adventure.

Havanese:

Despite their long, silky coats, these happy little cuties shed less than you think, making them a hypoallergenic pick for many owners. Pair that with their bouncy personalities and hallmark curled-over tails, and it's the total package.

Pekingese:

A total couch potato, Pekingese dogs love a laidback lifestyle with plenty of cuddles. These dogs also have noble origins, getting their name from their home in the Imperial Palace in Peking (later named Beijing).

Chinese Crested:

If you want a unique-looking dog, look no further. This "cat-like" animal prefers a quiet household but still enjoys pleasing its owner. The pups come in two varieties: the hypoallergenic Hairless and the full-coated Powderpuff, which can both occur in the same litter.

Miniature Pinscher:

Lively and alert, these high-spirited canines are always on the go. Min Pins are known for their unique, fun-loving personalities, but that "big dog" demeanor can sometimes translate as aggression and frequent barking.

Italian Greyhound:

The slighter relatives of taller Greyhounds, these pets bring both the companionship of a toy dog and the athleticism of a hound. They're adaptable and affectionate; one Italian Greyhound named "Le Beau" even lived in the White House with President John Tyler.