This week the Carbon Trust launched a range of 20 carbon-labelled products at Tesco across four different categories. For the first time shoppers will be able to compare the impact of like for like products, a significant step toward carbon-conscious shopping. The last 12 months have seen an increasing drive from businesses to reduce greenhouse gas emissions in their supply chains . To calculate these emissions and so focus efforts to reduce them, the Carbon Trust has been working with Defra, BSI British Standards and companies to develop a single standard for this measurement, called the PAS 2050. However, it is not just the measurement of emissions that matters. Our collective challenge is to provide consumers with the information they need to make sustainable choices. Research shows that two thirds of consumers prefer to use products or businesses with a low carbon footprint . Tesco is one of nine partners participating, and the labels are now displayed across ranges of orange juices, potatoes, light bulbs and washing detergents. This allows consumers to begin to use their purchasing power to communicate with manufacturers and retailers over carbon. We hope that Tesco's move will catalyse further action from others to drive more and more carbon out of their supply chains . The grocery and retail sector has a major role to play in accelerating the UK's transition to a low carbon economy. My message to the industry is, by working together, we can achieve much more.