Also known as the Chinese Lion Dog, or the Chrysanthemum Dog, the Shih Tzu is considered to be one of the oldest dog breeds in the world. However, despite the fact that this breed has been around since 800 B.C., the American Kennel Club did not recognize them until 1969!
Originally from China, the Shih Tzu is a special breed of small dog that is best recognized for its large dark eyes and short muzzle. This dog is mostly judged on the size and shape of its head when competing in a show. It should be large, round and their ears should blend into the rest of their hair.  Normally, the Shih Tzu is 8 to 11 inches tall, and weighs between 9 and 16 pounds. In addition to its heavily-furred tail, the Shih Tzu has long fur covering its ears. Its long coat usually grows quickly, so regular grooming is necessary. It is recommended that the owner of the Shih Tzu comb their hair daily because of how easily it can mat. Despite their long hair, they shed very little.
Sometimes, Shih Tzus are referred to as Chrysanthemum Dogs because their hair grows in every direction. It is for this reason that they resemble the Chrysanthemum flower.
This breed is preferred by dog lovers because of their adorable temperament and personality. They are usually outgoing, alert, loyal and affectionate. Furthermore, the natural alertness of this breed makes them excellent watch dogs. However, these dogs are not easily trained and the owner must begin at a very young age. 
Shih Tzus are also loved because of their very friendly nature. They can interact well with the adults, children, and other dogs. Some Shih Tzus are known for being courageous, clever, spunky and playful.  At home, they follow people wherever they go. In addition to being naturally good-natured, they are known to be highly adaptable – they can live in mansions or tiny apartments.  Unlike other breeds, adopting a Shih Tzu doesn’t necessarily require a yard. However, they do need exercise and it should be remembered that they are sensitive to heat because of their thick coat.
Shih Tzus are primarily bred to be great pets. Research shows that healthy Shih Tzus can live anywhere from 10 to 16 years, especially when all of their needs are met.
 Jo Ann, Your Happy Healthy Pet: Shih Tzu, p. 12.