Architect William McDonough captures the spirit of design to dematerialize in his oft-cited quote: We should recycle, but it is not the first thing we should do, it is the last. Redesign first, then reduce, and finally recycle if there is no alternative.(Thorpe, 1999, p.27). John Young (2000) of the Materials Efficiency Project fleshes out this perspective with the following hierarchy of priorities for materials efficiency that I have adapted with some reference to construction materials: 1. Materials use avoidance: this includes scrutiny of consumption needs themselves do we really need to build this?and voluntary simplicity. It includes a focus on selling services, rather than products. It also includes the redesign of products, buildings and settlements to dispense with superfluous materials. The great efficiencies resulting from ecological urban design and mixed-use development are in this category. Certain new engineered wood products (if non-toxic) can displace massive amounts of conventional wood. 2. Increased intensity of product use: Product durability and all kinds of sharing are included here, and thus there is some overlap with category #1. Co-housing developments with shared facilities, for example, can substantially reduce the volume of materials use. 3. Reuse-based material cycles: Repair, reuse and remanufacturing are in this category, and in building there is vast potential for deconstruction (the disassembly of buildings) and the reuse of building materials. One step further is the design of buildings to be easily changed, repaired and disassembled.