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
Tonight sees the first episode of 'Top Dogs', a new six-part series where we visit one world's leading dog-training academies - the Malpeet K9 Academy.
Dogs at the centre are prepared for a life sniffing out drugs and explosives.
We'll meet one of the dogs tonight on our 6pm news programme.
You can watch the first episode of 'Top Dogs' at 8pm tonight on ITV.