American Institute in Taiwan

The American Institute in Taiwan (AIT) serves as the representative office of the United States in Taiwan. The establishment of diplomatic relations with the People's Republic of China in 1979 required acknowledgment of the One-China policy and termination of diplomatic relations with the Republic of China. However, the AIT serves to assist and protect US interests in Taiwan in a non-official manner.
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The AIT is a non-profit corporation that represents U.S. commerical,
cultural, and other interests in Taiwan in lieu of an embassy. In 1979,
the United States terminated formal diplomatic relations with Taiwan when
it recognized the People's Republic of China as the sole legal government
of China. AIT was authorized to continue commercial, cultural and other
relations between the United States and Taiwan. AIT headquarters are
located in Arlington, Virginia; constitutent offices are in Taipei and
Kaohsiung, Taiwan.