The Australian Shepherd, the cowboy's herding dog of choice, is a medium-sized worker with a keen, penetrating gaze in the eye. Aussie coats offer different looks, including merle (a mottled pattern with contrasting shades of blue or red). In all ways, they're the picture of rugged and agile movers of stock. Aussies exhibit an irresistible impulse to herd, anything: birds, dogs, kids. This strong work drive can make Aussies too much dog for a sedentary pet owner. Aussies are remarkably intelligent, quite capable of hoodwinking an unsuspecting novice owner. In short, this isn't the pet for everyone. But if you're looking for a brainy, tireless, and trainable partner for work or sport, your search might end here.