The reorganization of State Department offices was mandated under the Foreign
Affairs Reform and Restructuring Act of 1998; this reorganization included the
integration of the former Arms Control and Disarmament Agency (ACDA) in
April 1999 and the merger of the United States Information Agency (USIA) into the State
Department, which began on October 1, 1999:
State Magazine: USIA Merger (web archives)
http://www.state.gov/www/publications/statemag/statemag_sept99/feature1.html
Integration of ACDA (web archives)
http://www.state.gov/www/global/arms/
Should you have any difficulty contacting an office during this period of
transition (which affects many different offices, including ACDA and USIA, you may wish to directly contact
the State Department Locator Service for assistance at 202-647-4000.
For more information about the reorganization, please see:
Foreign Affairs Reorganization Fact Sheet (web archives)
http://www.state.gov/www/global/general_foreign_policy/fs_981230_reorg.html
Foreign Affairs Agencies Reorganization (reports and statements) (web archives)
http://www.state.gov/www/budget/index.html#reorganization
Also, an archived version of the former ACDA web site as it stood before reorganization is available
in the State Department's Electronic Research Collection Archive site:
http://dosfan.lib.uic.edu/acda/