The first cycle of the OECD Programme for International Student Assessment (PISA) was conducted in 2000. Students in 32 countries were surveyed to assess their reading literacy, mathematical literacy and scientific literacy. It is essential in an international study of this type that the assessment materials be culturally appropriate for the many participating groups. They must also be linguistically equivalent, and make sense psychometrically for individual countries as well as for the group of participants as a whole. This article discusses the steps taken to attain cultural relevance and appropriateness in the reading literacy construct, and in the stimulus materials and items which operationalizeit. It explains the influence of multilingual considerations on the development of the reading literacy assessment instrument and notes some psychometric procedures used to maximize the validity of the instrument in an international context.