Abstract: This invention is a heat conserving or cooling suit enclosure of plastic sheet for a patient undergoing a medical procedure or for a patient with hypothermia or hyperthermia from any cause. The enclosure is preferably compartmentalized to allow the sealing off of non-effected parts of the body to reduce or increase heat loss and if necessary, to actively heat or cool those parts while permitting full access to the areas which are the subject of a surgical procedure. The enclosure may have separate elements for the arms and legs with each of the compartments having a longitudinal preferably upstanding seam, readily openable to allow access to those areas for manipulation and procedures and which can be resealed around tubes and conduits inserted into or attached to the patient. The patient is placed upon each open component part of the enclosure while it is flat and the part is subsequently closed about the patient by engaging the longitudinal seams.