"In April 2009, President Obama announced an international initiative to secure all vulnerable nuclear materials worldwide within 4 years. Nonproliferation programs administered by the National Nuclear Security Administration (NNSA) are working to secure nuclear materials in Russia and other countries. GAO assessed (1) U.S. governmentwide efforts to implement the President's 4-year nuclear material security initiative; (2) the status and challenges, if any, of NNSA's nuclear security programs in Russia; and (3) NNSA efforts to secure nuclear materials in countries other than Russia. To address these issues, GAO analyzed U.S. nuclear security strategies and plans and interviewed U.S. and Russian government officials. This report summarizes the findings of GAO's classified report on securing nuclear materials worldwide.