Chihuahua

Chihuahuas are one of America's most popular small dogs. Prominently featured in major films like Legally Blonde and Beverly Hills Chihuahua, Chihuahuas are often stereotyped as "girlie dogs." But it's a mistake to assume that their portable size and cute looks means these tiny dogs lack personality. The American Kennel Club describes the breed as "Graceful, alert and swift-moving with a saucy expression, Chihuahuas are highly intelligent and should not be underestimated even though small in size." Chihuahuas have a reputation for feistiness, too.