Working Group is the name of a breed Group of dogs, used by kennel clubs to classify a defined collection of dog breeds. Most major English-language kennel clubs include a Working Group, although different kennel clubs may not include the same breeds in their Working Group. Working Group does not define one particular type of dog. It is not a scientific classification. Working Group is not a term used by the international kennel club association, the Fédération Cynologique Internationale, which more finely divides its breed groupings by dog type and breed history.

There are as many types of work for dogs as there are types of dogs. Lapdogs may work as therapy dogs, herding dogs may work livestock, and guard dogs may work at defense of people or property. Most dogs today are kept as pets rather than for any particular work. Modern purebred breeds developed from large guardian, herding and Spitz type dogs are usually quick to learn, and these intelligent, capable animals make solid companions. Their considerable dimensions and strength alone, however, make many working dogs unsuitable as pets for average families. By virtue of their size alone, these dogs must be properly trained.

In general, kennel clubs assign larger breeds that are engaged in some sort of physically active work to their Working Group. In areas of the world where livestock production is economically important, pastoral dogs are placed in the Working Group. In the rest of the world, such dogs are placed in a Herding Group or Pastoral Group, and dogs that were traditionally bred for guarding, rescue, police or messenger work, as well as large Spitz type dogs, are placed in the Working Group. These breeds may also be placed in a kennel club's Utility Group.