Mountain rescue dogs vastly increase the chances of finding lost climbers and hill walkers.
But how do you go about training a dog to pick up the scent of another human and inform you where they are?
In the video below, Richard Beech shows us how he trains his dog Kellin to perform mountain rescue duties.
He and Kellin have been working as a partnership in the Welsh mountains for 11 years.
Scroll down to take a look...