Clothing is a portable micro-environment of the human body. This paper confirms how effective clothing is a tool for the human body to adapt to various climates on the earth from cold to hot. First of all, from a spatial stand point, the relationship between climate and the characteristics of folk costumes throughout the world, and from a perspective of time, the seasonal changes in Japanese clothing culture (koromogae) were briefly summarized. Then, the methods and the results through four different approaches which have conducted in our laboratory in order to develop the functional, climate adaptable and comfortable clothing were introduced. In the behavioral approach on climatic adaptability based on clothing, the dressing behavior of urban residents was examined with a fixed-point observation method using photography in order to survey the connection between clothing and climate in modern society. In the physical approach, the development of thermal/sweating thermal manikins in our laboratory and the evaluation of Cool-Biz products developed by fiber/apparel companies using a sweating thermal manikin “JUN” were introduced. In the physiological approach to develop climate adaptable clothing, physiological basic data on the human body in different climates, especially a distribution of skin temperature and sweating rate over the skin surface were described. In the psychological approach, local thermal sensation and humid sensation over the skin surface were examined and the research methods and the results obtained were briefly introduced.