This American breed — that's right, it's not from Australia — developed on the vast ranches of the West, where shepherds bred together the best bobtailed herding dogs until they'd created a new one that thrived in the high altitudes. Thus Aussies are comfortable in all types of weather.
Weight: 40-65 lbs.
Best Qualities: These are highly intelligent, motivated dogs that can run for hours, and are so good with kids that farmers have trusted them as babysitters. "These dogs have a high desire to please," says Colorado breeder Carol Ann Hartnagle.
Drawbacks: Aussies have energy to burn, so they need to run. They also shed their undercoat regularly, so you'll need a good vacuum.
What to Do With Them: Just about anything outdoors.