Working dogs are large, muscular dogs that pull carts and sleds, perform rescue work, and act as guide dogs for the blind. Some working dogs are trained in police work to use their sense of smell to locate contraband, such as drugs and explosives, at airports; they are also used for patrol work. Some breeds make dependable watchdogs, warning of the approach of strangers by barking. Other breeds are used as guard dogs to protect homes and other types of property. Guard dogs are typically aggressive and are trained to attack intruders. Although there is no one typical breed for this group, it includes many of the northern-and mastiff-type dogs.

The northern types, or Spitz-type dogs, have wolflike faces; tight-lipped muzzles; erect ears; muscular bodies; double coats; and curled or plumed tails. A typical breed is the Alaskan Malamute.

Mastiff-type dogs are powerful, massive animals with square, deep muzzles, which are typically dark and wrinkled; wide-set legs, and short, smooth coats. A typical breed is the bullmastiff.

a northern-type dog native to Japan. It is a large, heavy-boned breed with a thick double coat that is typically white, brindle, and brown. The Akita has erect, triangular ears and deep-set eyes. The tail curls over the back. Akita were originally bred to hunt bears and deer. They are good house pets and capable guard dogs. Ideal height: males, 26 to 28 inches (66.0 to 71.1 cm); females, 24 to 26 inches (61.0 to 66.0 cm). Typical weight: males, 85 to 100 pounds (38.6 to 45.4 kg); females, 75 to 85 pounds (34.0 to 38.6 kg).

a northern-type dog originally bred to pull sleds by the Malamutes, a tribe of American Indians in Alaska. The dog has erect, wedge-shaped ears; almond-shaped eyes; and a plumed tail that curls over the back. The double coat is light gray to black with white markings on the legs, feet, and underparts. Unusual markings on the face form a cap or mask. The Alaskan Malamute is good with children. Ideal height: males, 25 inches (63.5 cm); females, 23 inches (58.4 cm). Ideal weight: males, 85 pounds (38.6 kg); females, 75 pounds (34.0 kg).

a northern sled dog that resembles a Samoyed. It is among the oldest dog breeds, descended from a breed known to have existed in the New Stone Age. The dog has a long, white coat, a square, muscular body, a plumed tail, a wedge-shaped head, and prick ears. The neck is covered by a lionlike mane. This dog is intelligent, has a gentle temperament, and is an obedient pet. Though playful with children, it is an excellent guard dog, barking aggressively to announce intruders. Typical height: Two sizes are recognized—miniature, 12 up to 16 inches (30.5 to 38.1 cm) for males; and standard, 16 to 20 inches (40.6 to 50.8 cm) for males. Females are slightly smaller in both cases. Typical weight: miniature male, 12 to 20 pounds (5.4 to 9.1 kg); standard male, 20 to 35 pounds (9.1 to 15.9 kg); miniature female, 10 to 18 pounds (4.5 to 8.2 kg); standard female, 18 to 32 pounds (8.2 to 14.5 kg). This breed is recognized by the UKC but not by the AKC.

an ancient draft dog of Bern, Switzerland, originally bred to pull carts through the mountains. It has V-shaped, hanging ears and a thick tail. The long, silky hair is black with russet markings on the legs, cheeks, and chest, and over the eyes. White markings are found on the feet and chest, and at the tip of the tail. The dog is independent and needs obedience training. Ideal height: males, 24.5 to 27.5 inches (62.2 to 69.9 cm); females, 22.5 to 25.5 inches (57.2 to 64.8 cm). Typical weight: males, 80 to 105 pounds (36.3 to 47.6 kg); females, 75 to 90 pounds (34.0 to 40.8 kg).

a muscular, mastiff-type breed from Germany. It is popular in the United States as a pet and watchdog, and is also used for police work. The boxer was originally bred for bullbaiting and dog-fighting. It is named for the humanlike way it jabs with its forepaws when fighting. The ears are cropped and held erect, and the tail is docked. The short coat is fawn or brindle with white markings. Ideal height: males, 22.5 to 25 inches (57.2 to 63.5 cm); females, 21 to 23.5 inches (53.3 to 59.7 cm). Typical weight: males, 70 pounds (31.8 kg); females, 60 pounds (27.2 kg).

a powerfully built watchdog, originally; bred to guard English country estates against poachers. It has V-shaped, hanging ears; a tapering tail; and a wrinkled muzzle. The short, dense coat is red, fawn, or brindle. The ears are dark and there is a dark mask on the face. The bullmastiff can be independent and stubborn, and requires obedience training. Ideal height: males, 25 to 27 inches (63.5 to 68.6 cm); females, 24 to 26 inches (61.0 to 66.0 cm). Ideal weight: males, 110 to 130 pounds (49.9 to 59.0 kg); females, 100 to 120 pounds (45.4 to 54.4 kg).

a German dog named for Louis Dobermann, the developer of the breed. It is an intelligent, muscular dog with a clean-cut appearance. It has been used in military work and police work, and as a guide dog for the blind. The Doberman pinscher has a wedge-shaped head, almond-shaped eyes, and tight lips. The ears are cropped and the tail is docked. The short, fine coat is black, red, blue, or brown with rust-colored markings on the face, legs, and feet. Ideal height: males, 26 to 28 inches (66.0 to 71.1 cm); females, 24 to 26 inches (61.0 to 66.0 cm). Typical weight: males, 70 to 75 pounds (31.8 to 34.0 kg); females, 60 to 65 pounds (27.2 to 29.5 kg).

a German dog originally bred to herd cattle. It has a wedge-shaped muzzle. The ears are cropped and the tail is docked. The wirehaired double coat is solid black or pepper-and-salt. The hair forms eyebrows and a beard on the face. The dog is spirited, alert, and playful. Ideal height: males, 25.5 to 27.5 inches (64.8 to 69.9 cm); females, 23.5 to 25.5 inches (59.7 to 64.8 cm). Typical weight: 65 to 95 pounds (29.5 to 43.1 kg).

a huge mastiff-type dog, originally bred to hunt wild boars. It has a long muzzle; ears that fold over or are cropped; and a long, thin tail. The short coat is brindle, fawn, blue, black, or harlequin. Great Danes make good pets and good watchdogs, their size alone being enough to scare away intruders. If provoked, they may attack. Ideal height: males, at least 30 inches (76.2 cm); females, at least 28 inches (71.1 cm). Typical weight: males, 135 to 150 pounds (61.2 to 68.0 kg); females, 120 to 135 pounds (54.4 to 61.2 kg).

an ancient French breed developed to guard sheep and pull sleds in mountainous regions. It is a northern-type breed with drop ears, a bushy tail, and a large, wedge-shaped head. The thick, double coat is solid white or white with badger, gray, or tan markings. The Great Pyrenees makes a good companion and good family dog. Ideal height: males, 27 to 32 inches (68.6 to 81.3 cm); females, 25 to 29 inches (63.5 to 73.7 cm). Ideal weight: males, 100 to 125 pounds (45.4 to 56.7 kg); females, 90 to 115 pounds (40.8 to 52.2 kg).

a large white dog of Hungarian origin originally bred to guard sheep. The dog has hanging, V-shaped ears and a long tail. The coat is composed of long, tassel-like cords that cover the eyes and face, and hang down along the back, legs, and tail. The komondor makes a good watchdog. Ideal height: males, at least 25.5 inches (64.8 cm); females, at least 23.5 inches (59.7 cm). Typical weight: males, 95 pounds (43.1 kg); females, 80 pounds (36.3 kg).

a solid white breed with a thick, double coat. It is originally from Tibet, and was popularized in Hungary in the 15th century. The dog has almond-shaped eyes, ears that fold over, and a long tail that hangs down. The kuvasz is active and intelligent. It is good with children and makes a good guard dog. Ideal height: males, 28 to 30 inches (71.1 to 76.2 cm); females, 26 to 28 inches (66.0 to 71.1 cm). Ideal weight: males, 100 to 115 pounds (45.4 to 52.2 kg); females, 70 to 90 pounds (31.8 to 40.8 kg).

an ancient European and Asian breed popularized in England. The mastiff has a broad head with a short muzzle and ears that fold over. The short, smooth double coat is apricot, silver-fawn, or dark brindle; the ears and muzzle are dark. The mastiff was bred for dogfighting, and is now primarily kept as a watchdog. Ideal height: males, at least 30 inches (76.2 cm); females, at least 27.5 inches (69.9 cm). Typical weight: males, 180 pounds (81.6 kg); females, 170 pounds (77.1 kg).

a large water dog with webbed feet and an oily, water-resistant coat. It was originally used to pull carts and carry packs, and to help fishermen with their nets. It is valued for its ability to rescue persons in water. The dog has a massive head; deep-set eyes; small ears that fold over; and a long, bushy tail. It is typically black, but the Landseer strain is white with bronze or black markings. The Newfoundland is intelligent and good with children. Typical height: males, 28 inches (71.1 cm); females, 26 inches (66.0 cm). Typical weight: males, 130 to 150 pounds (59.0 to 68.0 kg); females, 100 to 120 pounds (45.4 to 54.4 kg).

a medium-sized breed that resembles a poodle. This unusual dog was originally bred by Portuguese fishermen to retrieve nets and dive for fish. With its webbed feet and thick, water-repellent coat, it is well-adapted to the water. The dog's ears are heart-shaped and hang down; the tail tapers at the tip and arches over the back when the dog is excited. The wavy or curly coat is black, brown, or grayish-white. It is professionally clipped like that of the poodle. The Portuguese water dog sheds very little and is a good family dog. Ideal height: males, 20 to 23 inches (50.8 to 58.4 cm); females, 17 to 21 inches (43.2 to 53.3 cm). Ideal weight: males, 42 to 60 pounds (19.1 to 27.2 kg); females, 35 to 50 pounds (15.9 to 22.7 kg).

a mastiff-type German breed originally used to drive cattle, and now used in police work and as a guard dog. It is a robust dog with a broad head and chest. It has rectangular, hanging ears, and the tail is docked. The short coat is black with rust or mahogany markings on the face, chest, and legs. Ideal height: males, 24 to 27 inches (61.0 to 68.6 cm); females, 22 to 25 inches (55.9 to 63.5 cm). Typical weight: males, 115 pounds (52.2 kg); females, 100 pounds (45.4 kg).

a rescue dog bred by monks at a hospice on the Great St. Bernard Pass in the Swiss Alps. St. Bernards are believed to have rescued more than 2,000 persons lost in Alpine storms. They began their rescue work in the 17th century; it was discontinued in the 20th century, with the virtual disappearance of foot travelers. The dog is popularly depicted with a cask of brandy around its neck, but it did not carry such a cask during rescue missions. The St. Bernard is the heaviest breed. It has a large head with drop ears, a short muzzle, and pronounced wrinkles on the forehead. The tail is long and bushy, and turns up at the tip. Two varieties of coat are recognized by the AKC: (1) long-haired, with a ruff around the neck and feathering on the legs and tail; and (2) short-haired, with thick, short hair over the entire body. The coat is red and white or brindle. There is a white blaze on the forehead and a dark mask around the eyes. The St. Bernard makes a good watchdog. Ideal height: males, 27.5 inches (69.9 cm); females, 25.5 inches (64.8 cm). Typical weight: males, 165 pounds (74.8 kg); females, 145 pounds (65.8 kg).

a northern-type breed with a pure white or cream-colored coat. It was bred to herd reindeer and pull sleds. During ancient times, the breed was taken to northern Siberia from Iran by the nomadic Samoyed people. The double coat forms a ruff around the neck and shoulders, and the bushy tail curls over the back. The dog has a wedge-shaped head and erect, triangular ears. The Samoyed's lips curl up at the corners, giving it a smiling expression. It makes a good companion. Ideal height: males, 21 to 23.5 inches (53.3 to 59.7 cm); females, 19 to 21 inches (48.3 to 53.3 cm). Typical weight: males, 55 to 75 pounds (24.9 to 34.0 kg); females, 40 to 55 pounds (18.1 to 24.9 kg).

a northern-type breed native to northeastern Siberia (where it is called the Chuchi).

a compact, squarely built dog bred to hunt rats. It has bushy whiskers and eyebrows, and a mustache. The stiff, wirehaired coat is pepper-and-salt or solid black in color. The ears are cropped and the tail is docked. The standard schnauzer makes a good guard dog and pet. Ideal height: males, 18 to 19.5 inches (45.7 to 49.5 cm); females, 17.5 to 18.5 inches (44.5 to 47.0 cm). Typical weight: males, 40 to 50 pounds (18.1 to 22.7 kg); females, 30 to 40 pounds (13.6 to 18.1 kg).