The Carbon Trust

Last month, retail giant Tesco became the world’s first supermarket to stick carbon impact labels on its own-brand products.

Who's behind it all?

The UK's Carbon Trust, with its proprietary carbon-labeling scheme that it brought to market in 2007.

The ubiquitous "Carbon Trust" name has been bouncing around the Web for ages.

So who are they exactly -- and what else are they doing?