"Open Doors" is a long-standing, comprehensive information resource on the almost 565,000 international students in the United States in 2005/06 and on the nearly 206,000 U.S. students who studied abroad for academic credit in 2004/05. The Institute of International Education, one of the largest and most experienced U.S. higher education exchange agencies, has conducted an annual statistical survey of the internationally mobile student population in the United States since 1948, with support from the U.S. Department of State's Bureau of Educational & Cultural Affairs since 1972.