The U.S. State Department Central Files are the definitive source of American diplomatic reporting on political, military, social, and economic developments throughout the world in the 20th century. Concentrating exclusively on those Central Files that have not been microfilmed by the National Archives or other publishers, UPA's microfilm editions of the Central Files nonetheless dwarf the State Department's very selective volumes of the Foreign Relations of the United States (FRUS). Containing less than one percent of the material in the Central Files, FRUS focuses on U.S. relations with individual countries but does not include coverage of many of the key topics to which the majority of the original files are devoted. Each part of the Central Files contains a wide range of materials from U.S. diplomats in foreign countries: special reports on political and military affairs; studies and statistics on socioeconomic matters; interviews and minutes of meetings with foreign government officials; court proceedings and other legal documents; full texts of important letters, instructions, and cables sent and received by U.S. diplomatic personnel; voluminous reports and translations from foreign journals and newspapers; and countless translations of high-level foreign government documents. The Central Files also illuminate the internal affairs of foreign countries. For each country there are thousands of pages arranged topically and chronologically on crucial subjects: political parties and elections, unrest and revolution, human rights, government administration, fiscal and monetary issues, labor, housing, police and crime, public health, national defense, foreign policy-making, wars and alliances, education, religion, culture, trade, industry, natural resources, and more. Numerous State Department files describe in detail this decade of nearly constant warfare and civil infighting, an era of growing military expenditures and worsening economic stagnation. Of particular interst are thousands of pages of reports from scholar-diplomats who visited the Communist forces, interviewed Communist leaders, and analyzed the Kuomintang-Communist struggle and its likely impact on the future of China.