This report presents testimony by the U.S. Government Accountability Office (GAO) exploring the Federal Government's efforts to address terrorist safe havens. The GAO found that while the U.S. Department of State (DOS) currently identifies terrorist safe havens, it does not assess them at the level of detail recommended by Congress. In its August 2010 report, DOS identified 13 terrorist safe havens in foreign countries, yet none of the assessments included information on 1 of the 4 elements recommended by Congress - the action taken by the governments of those countries identified as terrorist safe havens to prevent the trafficking of weapons of mass destruction through their countries. The GAO also found that about a quarter of the assessments lacked another element recommended by Congress - the actions of the governments of the identified countries to cooperate with U.S. antiterrorism efforts. In addition, GAO found that the Federal Government has not more completely addressed reporting requirements to identify U.S. efforts to prevent terrorists from obtaining safe haven. The primary recommendation from the GAO regarding the U.S. efforts to address terrorist safe havens centers on improving reporting by DOS and the National Security Council on their assessments of U.S. efforts to address terrorist safe havens. Tables and appendixes