This book covers a specific chapter of integrative physiology, which is usually neglected in physiology textbooks, and which has received little attention in the past as a dedicated subject of publication. Nice deep textbooks of altitude medicine or aviation and space medicine or diving medicine can be found, that cover the needs of highly specialised clinicians and investigators. However, to the best of our knowledge, this is the first time that the subject of human adaptation to special environments is proposed and treated in a comprehensive yet rigorous manner for the sake of a wider audience. The text acknowledges historical contributions, provides up-to-date information, describes separately basic and/or historical notions perhaps less treated than needed in classical textbooks, provides significant bibliographic material for a deeper study of the treated subjects, establishes continuous bridges between practice and physiological knowledge, and highlights special contributions from Italian investigators and institutions.