The Mine Safety and Health Administration (MSHA), the National Institute for Occupational Safety and Health (NIOSH), the Federal Mine Safety and Health Review Commission, the Department of Labor's Office of the Solicitor, the states, and the mining industry share responsibility for ensuring mine safety. GAO examined the challenges underground coal mines face in preparing for emergencies, how well MSHA oversees mine operators' training efforts, how well MSHA and NIOSH coordinate to enhance the development and approval of mine safety technology, and how civil penalties are assessed. To address these issues, GAO surveyed a representative sample of active underground coal mines, analyzed agency data, conducted site visits, and talked with agency officials and other experts. The survey results are estimated at the 95 percent confidence level.