This chapter describes the procedures used to analyse and scale the International Civic and Citizenship Education Study (ICCS) international and regional test items that were administered to measure students’ civic knowledge. The chapter covers the following topics: the scaling model used to analyze and scale the test items; test coverage and item dimensionality; assessment of item fit; assessment of scorer reliabilities for open-ended items; differential item functioning by gender; review of cross-national measurement equivalence; international item adjudication; international item calibration and test reliability; international ability estimates (plausible values and weighted likelihood estimates); estimation of changes in civic content knowledge between 1999 and 2009; and regional test items for the European and Latin American modules.