During 1999, researchers surveyed nearly 90,000 14-year-old students in 28 countries. Findings for this age group were released in 2001 and reported in Citizenship and Education in Twenty-eight Countries: Civic Knowledge and Engagement at Age Fourteen (Torney-Purta, Lehmann, Oswald, & Schulz). In the following year, over 50,000 upper secondary students (ranging in age from 16 to 19 years) from 16 countries received a similar test and the same survey of civic concepts and attitudes. Findings for the upper secondary students were released in 2002 and reported in Civic Knowledge and Engagement. An IEA Study of Upper Secondary Students in Sixteen Countries (Amadeo, Torney-Purta, Lehmann, Husfeldt, & Nikolova). This latest technical report will enable fellow researchers in the field to evaluate published reports, monographs and articles based upon these data and to conduct their own analyses of the international data sets available from IEA. This volume includes detailed information on instrument development, translation procedures, field operations, quality assurance procedures, sampling design, data management, database construction, weighting procedures, scaling methodology and reporting of data from the survey.