During the last 40 years, a large number of international comparisons of educational achievement in different subject areas have been carried out by organisations such as the IEA and the OECD. Both the number of studies, and the number of participating countries in each study, are increasing. The results of these studies have had a considerable impact on educational policy, and the data collected is a valuable resource for research. The data is of a high quality, and the data collection has been performed with advanced techniques for sampling and measurement. However, these techniques also make the data sets difficult to analyse, which is one reason why the potential of the data has not been fully exploited in research. The purpose of the project is to improve opportunities for analysing data from the comparative studies. This will be done through the creation of databases, particularly for the older IEA studies, and through the creation of new variables, which will be achieved through a combination of other variables, in order to reach a higher level of interpretability and precision. The project will also engage in the development of analytical competence through courses, workshops, and seminars.