SAR dogs are highly trained to use their strong sense of smell to locate missing people. They can be classified as air scent dogs, which search wide areas for any human scent, or trailing dogs, which follow a specific person's scent from an article of clothing. SAR dogs work in various terrains and scenarios to find lost hikers, children, or victims of crimes or disasters. They are deployed as quickly as possible to maximize success and can search areas equivalent to 20 humans. Proper training, intelligence, stamina and drive make certain breeds like German Shepherds and Labs ideal for the work. Retired SAR dogs often remain with their handlers or are adopted to experienced homes.