When it comes to reducing carbon emissions, it is difficult to conceive of an industry that faces a more complex challenge than the health service.
As HSJ discusses in this week's news analysis, procuring energy is just a fraction of the whole picture. Reducing emissions affects whether care should be delivered in hospitals or locally, where food is sourced from, the use of disposable clinical products, promoting cycling and public transport among visitors and its 1.3 million staff, cutting the use of treated water and replacing old buildings and boilers, to name just some of the issues trusts face.
There appears to be a chasm in the degree to which NHS organisations are getting to grips with the issue. While some have yet to make any meaningful progress - including several strategic health authorities - others are pursuing it with the zeal of religious converts.
This is one issue where managers are calling for more central support, to help them deliver the target of a 15 per cent cut in NHS emissions within 20 months.