This volume contains papers presented at the 37th Annual Symposium on Optical Materials for High-Power Lasers that was held at the National Institute of Standards and Technology in Boulder, Colorado, 19-21 September 2005. The symposium was cosponsored by Lawrence Livermore National Laboratory (USA), and the Pacific Northwest National Laboratory (USA). Cooperating organizations were the Center for High Technology Materials at the University of New Mexico (USA), Laser Zentrum Hannover e.V. (Germany), the National Institute of Standards and Technology (USA), QinetiQ (United Kingdom), and the College of Optics and Photonics, CREOL and FPCE, University of Central Florida (USA). The symposium, was attended by 145 scientist and engineers from China, France, Lithuania, Russia, France, Germany, Japan, the Netherlands, Russia, the United States, and the United Kingdom. One-third of the attendees and nearly half of the presentations were from abroad. A mini-symposium on Tuesday afternoon, that addressed damage issues associated with petawatt lasers, highlighted our growing interest in the emerging area. Including the mini-symposium, 87 papers were presented in oral and poster sessions.