So the government has jumped on the eco-labelling bandwagon set rolling by Tesco. On the face of it, this is good news. If David Miliband's statement of intent this week signals ministers are prepared to work collaboratively with the supermarkets on a standard label, it would be a real sign of progress in terms of trust in the supermarkets' power to do good.
Unfortunately, there's another scenario - that we get a repeat of the civil war that has erupted over front-of-pack nutrition labelling. It would be just typical if Tesco and Defra, or some quango, pulled in opposite directions on this - prompting an FSA-FDF style stand-off. While there may arguably be less scope for disagreement than in the traffic lights versus GDAs debate, just how keen will Asda, Sainsbury's and M&S be to collaborate on an eco-label initiative that's already got Tesco's stamp all over it? A raft of conflicting schemes is in no-one's interest.
These are not the only potential obstacles. I'm not convinced the consequences of an eco-label have been thought through. What happens if imports have lower carbon footprints than domestic products? If we are to believe a recent New Zealand study, which claimed that NZ dairy and lamb had lower footprints than their British equivalents, this is entirely possible - blowing the local-equals-low-carbon-footprint assumption out of the water. And will consumers really be able to cope with yet more labelling?
Miliband himself admits developing an eco-label "is not easy" and will take time. Tesco, too, has refused to put a timescale on its scheme, admitting it's likely to take years.
One thing is clear: if eco-labelling is to become a reality there needs to be genuine collaboration and consultation - not another escalating battle.