A conceptual description of a current mathematical model of the human body, analyzed in terms of heat transfer, is presented. This model is designed to predict thermal comfort responses of a person exposed to a particular indoor environment. Methods of heat exchange between the body core, the skin, and the surroundings are described. Formulations are also included for two parameters describing the environment-the mean radiant temperature and the convective heat transfer coefficient. Heat transfer equations and computer programs for this model are used to generate data for the study. Three applications for this model are discussed in terms of their effectiveness in achieving thermal comfort: the effect of radiant cooling panels, the effect of ceiling fans, and the effect a change in the person's metabolic rate. In each example, the temperature of the surroundings is displaced from a reference temperature where thermal comfort exists. Efforts to restore the sensation of comfort are examined and the results are illustrated in graphical and tabular form. Conclusions are drawn from the procedure and recommendations for future research are suggested.