because [these materials] are inferior in any way but due to historical forces that worked to reduce manual labor. The goal was not necessarily to reduce labour drudgery but to reduce labour costs and boost profits. This strategy of replacing labour with resources can not work in most of the world where labour is more obviously abundant and resources scarce. Those who consider natural building a marginal or fringe activity should contemplate that less than a third of the worlds population lives in buildings comprised of energy-intensive manufactured materials (Eisenberg, 2002). Between a third and half of the worlds people live in some kind of earthen structure (Kennedy, 2002b). In many areas of the world, earthen construction is stigmatized as backward or lower-class, despite the fact that earth can be among the most durable, economic and beautiful of building materials. Most of its techniques are readily amenable to participatory construction and design, and so complementary to the spread of democracy in planning, economics and technology. The continuing and expanded use of earth-building is a given for underdeveloped countries, but both global sustainability and equality depend upon greater portions of the first world rejoining the planet in a greater use of earth and other natural materials. Earth or clay is used to make bricks or block, to pour into forms, to stack up for walls, to use as infill for wood and bamboo frames, to create floors, etc. Among the most prominent realms of earthen building are pise or rammed earth; adobe; light-clay; cob; compressed earth blocks (CEB); and many other composite materials combining earth and other (usually fibrous) materials. What follows is a concise survey of these materials.