This third edition of the World Handbook of Political and Social Indicators is composed of four files, one aggregate data file (Part 1), and three events data files including a daily events political data file (Part 2), an annual political events data file (Part 3), and a new quarterly political events data file (Part 4). The aggregate data file (Part 1) is based upon data from the base years of 1950, 1955, 1960, 1965, 1970, and 1975. It contains political, economic, and social data and rates of change for 155 countries. Data are provided for central government current revenue and expenditure, gross national product and growth rates, imports, exports, and trade as a percentage of the gross national product, total military expenditure and manpower, public education, public health expenditure, energy consumption, coal, natural gas, and petroleum reserves and production, GINI measures of inequity, income inequity, sectorial inequity, coefficient of land inequality, political and civil rights indices, political and economic discrimination, the percentage of those discriminated against and its intensity, the proportion and intensity of separatism, voting behavior, the number of registered voters and voter turnout as a percentage of the adult population, the first five largest political parties, total legislative seats, total adult and working age population, population density, percentage of population in cities, agricultural density, health and nutrition measures, consumption measures, literacy, and school enrollment. Data are also provided for the percentage of the labor force in agriculture, industry, and the services, organized labor, industrial disputes and the number of working days lost, the life expectancy for males and females, infant mortality rates, and estimated birth rates and death rates, as well as the number of scientific authors, physicians per million population, total piped water, and newspapers, radios, television sets, and telephones per 1000 population. There are three files of events data in this collection. The first file records daily political events, the second aggregates these events to an annual file, and the third aggregates the same events into a quarterly file. The Daily Event Data file (Part 2) contains a variety of governmental change and political protest events for 139 countries. It records 38 kinds of domestic events including demonstrations, riots, strikes, assassinations, elections, referenda, and imposition of political restrictions, including censorship. Some of the 38 event types were only distinguished for the events occurring in particular periods. For example, the categories of bombing, ambush, raid, arrest, release of the arrested, imposition of martial law or curfew, and relaxation of martial law or curfew were added in 1978. The Annual Events Data file consists of summations of the occurrences of each type of event within each country on a year-to-year basis from 1948 to 1977. The annual totals are given for the same countries as in the daily file, with the exception of three countries. The Quarterly Event Data file consists of summations of the occurrences of each type of event within each country on a quarter-to-quarter basis. The 38 types of events coded in the quarterly events file have also been collapsed to 17 broader categories to maintain comparability with earlier editions of the handbook.