This proposal is directed toward a program to identify narrow band infrared obscurant materials, specifically for the 3-5 and 7-14 micrometer regions. The program will study materials that obscure by the reststrahlen absorptions in chemical compounds; by the vibrational absorptions found in many organic molecules; and by scattering in microstructured plastics materials. The output of the program will be a Technical Report, recommending one or more obscurant materials and outlining methods of manufacturing these materials. Narrow band infrared obscurants will have military applications in infrared threat sensor countermeasures. Similar commercial applications include hostage recovery applications by law enforcement personnel, and testing of break-in protection and security systems. Other commercial applications include pigments in high-emissivity paints and in wavelength-selective infrared transmitting materials for security systems and thermography. Low emissivity (high reflectivity) paints and makeup may also result from knowledge gained in this program