In this book we seek to approach the architecture-energy combination and its relationship to human comfort and the environment .There are chapters on thermal comfort, low energy architecture dealing with various criterion for comfort in different parts of the World. The book also seeks to understand how previous generations lived in harsh climates and without abundant sources of energy, yet managed to design and build appropriate dwellings providing both comfort and harmony with the environment. Other chapters deal with the bioclimatic concept in Vernacular Architecture; the major role which climate plays at different locations and how this can dictate the shape and form of the buildings and save energy; the importance of micro-climate and its various elements and usage; ventilation and its importance in buildings and the technology for modern architecture.