Lassie is an American television series that follows the adventures of a female Rough Collie dog named Lassie and her companions, both human and animal. The show was the creation of producer Robert Maxwell and animal trainer Rudd Weatherwax and was televised from September 12, 1954, to March 25, 1973. The eighth longest-running scripted U.S. primetime television series, the show ran for 17 seasons on CBS before entering first-run syndication for its final two seasons. Initially filmed in black and white, the show transitioned to color in 1965.

The Rough Collie is a long-coated dog breed of medium to large size that, in its original form, was a type of collie used and bred for herding sheep in Scotland. More recent breeding has focused on the Collie as a show dog, and also companion. The breed specifications call for a distinctive long narrow tapered snout and tipped (semiprick) ears, so some dogs have their ears taped when young. Rough Collies generally come in shades of sable and white, blue merle, tri-coloured, and colour-headed white.