Now unwanted dogs are being given a second chance to become man's best friend.
A new series from ITV focuses on a training academy in the hills above Bridgend where all different kinds of dogs are put through their paces - learning to sniff out explosives and drugs.
Crufts it is NOT, but the animals and their trainers love the work.
If you're in Wales, you can watch the first episode on ITV tonight at 8pm
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