Passive and Low Energy Ecotechniques (PLEA) presents the proceedings of the Third International PLEA Conference held in Mexico City, Mexico on August 6-11, 1984. The book includes papers on state-of-the-art selected topics aimed at providing a basic knowledge; country and regional or personal monographs to continue the exchange of national information which is an established feature of PLEA; and position papers for the topic seminars. The text also presents papers on vernacular shelter and settlement; case studies of new buildings and retrofits, urban and community planning and design, photovoltaic systems implementation, cooling systems, modeling and simulation, guidelines and tools for design and planning.