"Shopping is, on the whole, a transaction - something that demands very little interaction. But there's increasing evidence that people want shopping to be more of an experience; something that has meaning."

Swapping also tells the world a lot more about you than shopping does.

Not only does it make it very clear that you care about the environment, but because your currency is clothes you own rather than notes and coins, the experience automatically becomes a lot more personal and a lot more intimate.

"In a bartering economy, if people like what you have to offer, this validates your choices and, indirectly, validates you," says Prof Furedi.

Wearing your heart on your sleeve like this can be a daunting experience. Almost anyone who has been to a swap party will recount pre-party panic stories of their fears that all their clothes would be too big, too dowdy, too old or too unlovable to swap.

Inevitably this isn't the case, and more often than not people can have second thoughts about swapping an item when they realise that other people like it - as Camilla Yonge found.

"In the early days of the swap parties, we did have people suddenly deciding they didn't want to swap something after everyone else had exclaimed how lovely it was.

"Now there are rules. Once a garment is through the door and hanging on the rail, it no longer belongs to you. I tell people to bring things they love but don't wear - and they will get things they love but do wear."