Border Collies come from the hills along the Anglo-Scottish border, where shepherds developed them to gather sheep with a fixed stare, a low crouch and very little instruction. Today's dog is medium-sized, usually 30 to 55 pounds, with a rough or smooth double coat in black and white or a wide range of other colors and patterns.
Many are quick, eager learners that bond closely with their people, and herding instinct can show up as chasing, circling or nipping at fast-moving things. Dogs vary, though, and a Border Collie or mix may be calmer or more intense than the stereotype. Expect moderate shedding that peaks seasonally, and plan on daily activity plus training that gives the dog a job.