Shredding documents.

When DF died he had bank statements dating back to when he left the army in 1964 (he died in 2007). I put all but the last five years in a skip at the tip. The material was too old to be of any use to an identity thief. more recent documents I did shred.

Composting works well. Just stick a load of grass cuttings on top. No identity thief is so keen to be me, or you, that they are going to investigate the contents of your compost bin. And if they did, those worms would see 'em off.
Suspect the vast majority of this crime is online these days and not in dustbin.

tiggypiro - I like the bucket of water idea. We burned some old documents in one of the small garden burners, but unfortunately a couple of plastic staples had not been picked out beforehand. Our neighbour was furious about the smell - mind you, he does furious so well, that I believe it's his favourite expressed feeling.

I fill a basin with warm water and leave it all soaking into a kind of paper mache. Then I roll it into balls and stick in the bin! it works really well. Paper is unreadable and it is a lot less hassle. You could of course make something out of paper mache if you were so inclined!!!!

You can get it done 'professionally'. Just google paper shredding services. I had a load done recently as like opsimath it would have taken for ever.

We had this problem before we moved house eighteen months ago and as Elegran suggests we bought a small garden incinerator for about £18 and used that to burn LOADS of old documents.

It has actually proved a useful buy as we now use it to put garden waste in prior to taking it for recycling at the council waste disposal site. We have no space for a compost heap.

Or you could put them into a bucket of water for a day or two and then throw on the heap.

Tear them up roughly by hand and put them in the compost heap. Do it bit by bit if you have a lot. Just make sure you have garden stuff on top to stop them blowing away.

You could buy a little garden incinerator (just a metal dustbin on short legs with holes punched in the bottom and sides) and burn them in that. Better than an open fire with burning pages blowing around to the neighbours. If you have or could acquire an old galvanised bin or a metal container you could punch your own holes and stand it on four bricks. If it is an oil drum, make sure all the oil is thoroughly cleaned out of it.

Why not have a controlled mini bonfire? That is what I did when I discovered that I could not put old cheque books through the electric shredder.