Working Dogs.

The diverse dogs represented in this group were bred to perform a variety of tasks from guarding people, property, and livestock to pulling carts or sleds. In general, they’re strong, smart, and fearless and can be fun-loving or serious.
Because of their size and strength, they require a structured home life and firm, fair, consistent training by someone who can provide leadership without resorting to anger or physical force.

With a couple of exceptions, such as the Alaskan Malamute and Siberian Husky–breeds too people-oriented to be guard dogs–they’re protective. This protectiveness may become a problem if they don’t have lots of positive human interaction and the right training.
Some working dogs have smooth, easy-care coats, but many of them are Nordic or mountain breeds with lots of thick fur. Most of these dogs are considered moderately to highly active.