As discussed in the opening chapter, building materials can play a transformative role not just because of the absolute volume and mass they represent, but how they are deployed to become our built environmentand so distributed in a fairly decentralized way everywhere we live and work. Changing the arrangement of their distribution affects the quality and efficiency of the entire economy. And because they have, compared to other products, such a long use phase in their life cycle, they influence development over a long time frame. In addition, next to food/nutrition, they are used to satisfy the most vital need we havefor shelter. For all these reasons and more, they can be a fulcrum to leverage change in the economy as a whole. The distributed or decentralized nature of green (or postindustrial) development should be a starting point for strategy to dematerialize and detoxify the economy. As John Lyle pointed out, this has special historical significance: whereas industrialism effected a shift in the economys prime productivity from landscape to machinery, postindustrialism does the reverse. A green economy decentralizes production into the landscape, and its biggest challenge is finding the right patterns, through which the economy essentially flows in the winds of natural process. This of course puts special importance on the built-environment. It also influences how we look at work and labour, which must also be more embedded in the community and landscapeand more connected to previously invisible activities in the informal non-cash and semi-cash economy. The point of this thesis has been, from an ecological design perspective, to synthesize possibilities for building materials in the key areas of production, consumption, recycling, evaluation and regulation. All too often these areas are