The author takes us on a concise tour through the well established principles of eco-design, and illustrates each with examples of vernacular dwellings from around the world. She then goes on to describe how these principles can be integrated into the design of a modern eco-house, and backs this up with examples and details from built and tested experimental houses. Some of the sections are extremely up-to-date; for example the chapter on photo-voltaics include information on national grid pricing policy, installation costs, as well as specifications for the necessary hardware. Almost enough, in fact, to use as a DIY manual. The book culminates in a series of case studies which inspire and illuminate. At no time did I feel that the presentation was dry; the text is well supported by diagrams, photographs and technical drawings, some of which are beautifully presented and very detailed. In addition, and unusually for a book based on somewhat unproven science, Sue Roaf is unafraid of committing herself to personal opinions. For anyone wanting to be told how to go about establishing a personal ecological philosophy, this book offers firm guidance. My only criticism is that sometimes more questions are raised than answered, but in a book of this size and for this price there is a limit to the amount of information that can be offered. There are certainly plenty of references to help further study. The information is never less than practical and so far I have not come across a better way to grasp the subtleties and contradictions of what makes an ecohouse.