Summary: Heroin use poses a growing threat to the United States. In recent years, the number of heroin users in this country has increased, the purity level of heroin on the street is significantly higher, and the number of heroin-related hospital emergency room episodes has soared. The majority of heroin used in the United States originates in Southeast Asia, most of which is produced in Burma. Although the U.S. heroin strategy calls for a regional approach focused on Southeast asia, stemming the flow of heroin will be difficult because of a lack of a meaningful U.S. program in Burma, the lack of Burmese government commitment to drug control efforts, and ineffective U.N. drug control efforts within Burma. The United States increasingly relies on international organizations, such as the United Nations, in countries such as Burma where the United States faces significant obstacles in providing traditional bilateral counternarcotics assistance. The United States has supported U.N. drug control projects in Burma, but these efforts have been unsuccessful in reducing opium production because of the small scope of the projects, lack of support from the Burmese government, and inadequate planning.