Border Collies come from the hills along the Anglo-Scottish border, where shepherds needed a dog that could gather and move sheep with speed, focus and very little instruction. They're medium-sized, usually 30 to 55 pounds, and agile, with a rough or smooth double coat. Black and white is the most familiar, but the breed comes in many colors and patterns.
Many Border Collies are eager learners who bond closely with their people, and that intelligence needs daily work to go with it. Some are reserved with strangers or sensitive to sudden noise, which is worth thinking about on busy blocks and in shared buildings. Dogs vary, and a mixed-breed dog may show only some of these traits, so spend time getting to know the dog in front of you.