The United States Department of Energy National Laboratories and Technology Centers is a system of laboratories overseen by the United States Department of Energy (DOE) for scientific and technological research. The primary mission of the DOE national laboratories is to conduct research and development (R&D) addressing national priorities: energy and climate, the environment, national security, and health. Sixteen of the seventeen DOE national laboratories are federally funded research and development centers administered, managed, operated and staffed by private-sector organizations under management and operating (M&O) contracts with the DOE. The laboratories and their research mission The DOE is the nation's largest sponsor of research in the physical sciences and engineering, and is second to the Department of Defense in supporting computer sciences and mathematics. Most of that research is performed by the national laboratories. Although the national laboratories form an integrated system, each of them has its individual mission, capabilities, and structure. The chart shows the nature of the research done at each laboratory. All 17 of the laboratories are listed below, along with the location, establishment date, and the organization that currently operates each. National Scientific User Facilities The DOE Office of Science operates an extensive network of 28 national scientific user facilities. A total of over 30,000 scientific users from universities, national laboratories, and technology companies use these facilities to advance their research and development. The staff of experts at each facility who build and operate the associated instruments and work with visiting scientists to mount experiments with them. This access and support is provided without charge to qualified scientific groups, with priority based on recommendations by expert review panels. All six research offices support scientific user facilities at national laboratories. History The system of national laboratories started with the massive scientific endeavors of World War II, in which several new technologies, especially the atomic bomb, proved decisive for the Allied victory. Though the United States government had begun seriously investing in scientific research for national security in World War I, it was only in this wartime period that significant resources were committed to scientific problems, under the auspices first of the National Defense Research Committee, and later the Office of Scientific Research and Development, organized and administered by Vannevar Bush. During the Second World War, centralized sites such as the Radiation Laboratory at MIT and Ernest O. Lawrence's laboratory at Berkeley and the Metallurgical Laboratory at the University