The thermal management of spacecraft would be enhanced by dynamic control over surface emissivity in the mid-infrared. In this SBIR program, Triton Systems proposes to demonstrate a flexible film material whose emissivity self-switches from a low value to a high value when the film temperature exceeds a preset value. The wavelength of peak emissivity can be engineered between 1.5 to 15 ?m as desired, and the transition temperature can be varied between 5-70 C. The film is easily engineered for different requirements, and if desired, different film characteristics could even be applied to different areas of the same spacecraft. No external power is required. The film substrate is a light weight flexible material that can be produced in large areas by roll-to-roll nanoimprinting. Triton Systems has substantial background in the computational design and fabrication of these types of switchable emissivity materials. In addition to NASA applications, the material will serve military needs such as IR signature control for ships, aircraft, UAVs or land vehicles, commercial needs in thermo-photovoltaics, and for energy efficiency in residential and commercial architectural uses for walls, roofs and windows.