Why GAO Did This Study.Whistleblowers play an important role in safeguarding the federal government against waste, fraud, and abuse, and their willingness to come forward can contribute to improvements in government operations. However, whistleblowers also risk reprisal, such as demotion, reassignment, and firing.This testimony discusses DODIGs progress in 1 taking actions to track and report on the timeliness of military whistleblower reprisal investigations, and 2 strengthening its oversight of the military services whistleblower reprisal investigations.GAOs statement is based primarily on information from May 2015 and February 2012 GAO reports on military whistleblower reprisal investigations. For those reports, GAO examined laws, regulations, and DOD guidance conducted detailed file reviews using representative samples of cases closed in fiscal year 2013 and between January 2009 and March 2011 analyzed DODIG and military service data for cases closed in fiscal years 2013 and 2014 and interviewed DOD officials. GAO also determined what actions DOD had taken through August 2016 in response to recommendations made in the 2015 and 2012 reports. What GAO RecommendsDOD implemented 15 of the 18 recommendations GAO made to improve and track investigation timeliness and strengthen oversight of the military services investigations, and is considering steps to implement the remaining three regarding standardized investigations and reporting to Congress.