The headquarters of the AIT is in Washington, D.C. and the AIT is headed by a chairman who resides there. The AIT also has an office in Taipei and a branch in Kaohsuing. The Director of the Taipei Office of the American Institute on Taiwan serves the functions normally associated with an ambassador. The current Taipei office Director is Douglas H. Paal, and the current Chairman of the AIT is Therese Shaheen.
The AIT exists because the United States as part of the one China policy does not officially recognize the Republic of China as the government of Taiwan and hence cannot open an actual embassy there.
See also: Foreign relations of Taiwan, Political status of Taiwan