The primary objective of this project is to analyze theoretically thermal responses in human subjects who are exposed to microwave radiation under various environmental conditions. Mathematical analysis of this problem can be divided into two major parts--one to compute specific absorption rates (SAR's) by solving the electromagnetic field equations and the other to compute temperature profiles by solving the heat conduction equation, including the effect of exogenous heating owing to the EM field. Physiological factors, such as metabolic heat generation, convection of heat by circulating blood, and vasomotor action, must be included in the thermal analysis. Whenever possible, validity of the model will be established by demonstrating that good agreement exists between corresponding theoretical and experimental results. The mathematical model will be used to analyze effects to be expected from human exposure to various representative microwave fields.