Hi We live in the countryside and are forever catching mice that come in, we use a trap called "Easy-set" made by a company called Growing success organics ltd, they are very good traps and the mouse does not suffer.
There's also a type called Trip-trap that not only catches the mouse alive (for releasing several miles away!) but is also, in my personal experience, 10 times more effective than the dreadful wire jobs which are supposed to kill but often just catch a leg or a tail.
I have bought a couple of Trip Traps from my local pet shop.
Thank you for your helpful hints (especially cleversod, but I can't leave doors open as you can't trust people round here and I'll come home to find only the mice left!) As it's a built-up area releasing them into the country would be a few hours away, any prefrence on foodstuff to lure with?