There was a time when the pit bull was one of the most popular family pets in the country. But today, the breed is more closely associated with gangs and violent dogfighting. Pit bulls have recently been responsible for more fatal attacks on humans than any other type of dog, making them among the most vilified -- and unwanted -- dogs in America. Cesar and his current pit bull companion, Junior, make the case that it's not just pit bulls but humans as well that need to be trained to get along. (Source: National Geographic Wild)