Pursuant to a congressional request, GAO reviewed the military services' investigations of training-related deaths, focusing on whether the services: (1) identified and investigated all training-related deaths; (2) ensured adequate independence of investigations; and (3) had systems for ensuring that corrective actions are taken. GAO found that: (1) between fiscal years 1989 and 1992, at least 700 uniformed personnel died while engaged in such training activities as swimming, parachuting, weapons training, and physical fitness exercises; (2) each of the services has regulations requiring it to conduct safety investigations of serious mishaps and each of the services has a central safety center that establishes and implements safety policies; (3) the services have not performed all required investigations of all training-related deaths because they do not investigate deaths due to natural causes, even if the deaths occurred during training; (4) the services have not conducted all required safety and legal investigations of fatal aviation and non-aviation training mishaps; (5) the services have adequate controls to ensure credible investigations and effective tracking of recommendations for corrective actions; and (6) the services do not have adequate procedures to ensure that legal investigations of training mishaps are independent and that recommendations are monitored until corrective action is complete.