Sheep dog in the context of Livestock guardian dog

A herding dog, also known as a stock dog or working dog, is a type of dog that either has been trained in herding livestock or belongs to one of the breeds that were developed for herding. A dog specifically trained to herd sheep is known as a sheep dog or shepherd dog, and one trained to herd cattle is known as a cattle dog or cow dog.

Sheep farming or sheep husbandry is the raising and breeding of domestic sheep. It is a branch of animal husbandry. Sheep are raised principally for their meat (lamb and mutton), milk (sheep's milk), and fiber (wool). They also yield sheepskin and parchment.

Sheep can be raised in a range of temperate climates, including arid zones near the equator and other torrid zones. Farmers build fences, housing, shearing sheds, and other facilities on their property, such as for water, feed, transport, and pest control. Most farms are managed so sheep can graze pastures, sometimes under the control of a shepherd or sheep dog.

The Border Collie is a British breed of herding dog of the collie type of medium size. It originates in the region of the Anglo-Scottish border, and descends from the traditional sheepdogs once found all over the British Isles. It is kept mostly as a working sheep-herding dog or as a companion animal. It competes with success in sheepdog trials. It has been claimed that it is the most intelligent breed of dog.