A refrigerant-containing bladder or container is positioned underneath the body. Heat absorbed from the body vaporizes the refrigerant, which expands to cooler remote regions of the bladder. Heat is then withdrawn from the edges of the container by thermally conductive pathways that distribute heat from this container to a cooler area that is not underneath the body. The cooled refrigerant condenses, and is returned to the regions of the device that are under or adjacent to the central and warmest parts of the body. The heavier and warmer portions of the body force the bladder to the lowest point. Alternatively, heat is transferred from the body via a specific highly thermally conductive layer or layers of material(s) that is (are) soft, pliable, and comfortable to sit or lie on. This layer joins conductive materials that are configured to transport heat and diffuse it to the cooler environment.