Correspondence, agenda, reports and other writings, subject and travel files, bibliographies, photographs, and other papers documenting Valeo's career as an East Asian specialist with the Library of Congress Legislative Reference Service, foreign affairs advisor to Senate Majority Leader Mike Mansfield, and secretary of the U.S. Senate; and Valeo's postretirement activities as a consultant in Chinese and Asian affairs. Includes material on political, economic, and military affairs in East Asia following World War II, especially in China, Japan, Korea, and the Philippines; senate files relating to Democratic party strategy, East Asian policy, the Vietnamese conflict, and the Commission on the Operation of the Senate; three senate leadership missions to China (1972-1976) for which he served as chief negotiator; and his directorship of studies on Asia sponsored by the United States Association of Former Members of Congress and coeditorship of a comparative study of the Japanese Diet (Kokkai) and the U.S. Congress (1983).