Abstract : This report summarizes work performed by Science Applications International Corporation (SMC) in fulfillment of a contract with the Defense Advanced Research Projects Agency. SMC's partner in this work was Lumileds, a major manufacturer of high power LEDs. Since SMC did not have a contractual relationship with Lumileds - which was agreed to by all parties at the beginning - SMC's performance on some tasks was ultimately limited by Lumileds' cooperation. One task was to investigate novel coatings that could protect and improve the performance of light emitting diodes (LEDs). Another task was to investigate methods to improve the stability and performance of a phosphor coating on an LED die. The final task was to develop original designs that could improve the external quantum efficiency of LEDs.