Walter E. Byrd is a research chemist in the Polymeric Materials Group of the Materials and Structural Systems Division (MSSD) of the Engineering Laboratory (EL) at the National Institute of Standards and Technology (NIST). Mr. Byrd received his bachelor of science degree in 1980 from Shepherd College, Shepherdstown, West Virginia, and, shortly thereafter, joined the Building Materials Division of the National Bureau of Standards. Currently, he is responsible for management and operation of the NIST SPHERE (Simulated Photodegradation by High Energy Radiant Exposure), a novel device for developing repeatable and reproducible methods for predicting the performance of materials. Previous research activities have included the study of degradation of solar collector materials and protective coatings, particularly focusing upon the identification of mechanisms of degradation and the use of analytical techniques for early detection of degradation. Analytical tools used include scanning electron microscopy, optical microscopy, thermography, thermal methods of analysis spectrophotometry, and chromatography.