Twenty-one IEA National Centers have collected information from a total of approximately 250,000 students, 50,000 teachers, and 10,000 schools. Included are surveys of student achievement in six subject areas: science, reading comprehension, literature, civic education, and French and English as foreign languages. From eight to nineteen countries participated in each survey by testing students at one or more of the following levels: 10 year olds, and students in the last year of pre-university schooling or programs of equivalent length. The data were collected between 1970-1974. The countries included are Australia, Belgium, Chile, Finland, France, West Germany, Great Britain, Hungary, India, Iran, Ireland, Israel, Italy, Japan, Netherlands, New Zealand, Romania, Sweden, Thailand, and the United States. In each of the surveys, in addition to student achievement data, information was obtained on the students' home and socio-economic backgrounds, interests, and attitudes. Information was also gathered on characteristics of the teachers and the schools in the surveys. Due to the magnitude of the study, interested users should request the introductory report that describes each file and the corresponding codebook prior to submitting their order.