The Sustainable Development Commission have published a report by Prof. Tim Jackson entitled Prosperity Without Growth. This is well worth reading and you can find it here
Jackson considers the mechanisms in the economy and how they might be adjusted to a zero growth scenario. His frank conclusion is that there is no macro-economic model for sustainability but that one is possible.
I find the most useful and stimulating parts of the report to be the chapter where he articulates the nature of the philosophical and psychological changes needed to arrive at a sustainable human society. Put simply, the growth paradigm is dead. Basing our economic and spiritual well being on the consumption of ever more stuff is a strategy for the extinction of modern human society. Why? Because we live on a planet of finite resources. There is no celestial conveyor belt from planet Argos. The old analogy of "space ship earth" could do with being revived. Everything we need we carry with us, the only external source of energy is the sun and all our waste has to be stored on board or recycled into something useful.
If we can accept that economic growth as defined by the last 100 years can not continue, then we can shift the debate to where it really matters: on what basis do we calculate value? How we do satisfy basic human needs such as a requirement for status and respect?
Some might argue that there is no need for this kind of existentialist self examination because technology will provide us with alternatives for oil, with greater efficiency of production and with a closed loop manufacturing process that minimises reliance on primary non renewable resources. This amounts to a gradual greening of the existing economy.
If nature operated by a process of gradual, incremental change then we could all carry on striving for the mansion, the SUV and the three overseas holidays a year confident that technology would deliver a sustainable consumerist society but nature has a tendency to do nothing much for a very long time then change very suddenly and very dramatically. Human societies usually follow the same pattern.
We don't have to repeat history or be caught out by nature: for once we are fore-warned and this time we have the depth of scientific, technological, sociological, spiritual, medical and psychological knowledge to side step the coming apocalypse like Shane avoiding a South African prop.
Prosperity Without Growth is an important step in the right direction but a lot more thinking by a lot more people is needed urgently if we are to transcend the death of consumerism.