The comprehensive Szeged research project on translation and post-editing competence has cross-sectional and longitudinal aspects, too. In this paper, the development of the competencies will be analysed with the help of a part of the longitudinal data. The section begins with listing the research questions, then moves on to describing the sub-sample which will be used in this longitudinal analysis. Next, materials and data collection procedures are referred to again, and finally, data analysis procedures are described in detail.