For over four decades, there were numerous connections between the Federation of German Catholic Youth (BDKJ) and Catholic youth in the GDR. These included both publicly known contacts and those that were largely hidden from the public eye. The latter pertained in particular to material aid, which provided an important foundation for the work of youth ministry in the GDR. Manfred Göbel has examined these connections, referred to as “partnership work,” and in doing so also describes the relationship between Catholic youth and the FDJ, as well as the BDKJ’s position on the reunification of the two German states and its actions during the final phase of the GDR. For this study, the records of the “Eastern Division” that existed at the time within the Federal Center for Catholic Youth were analysed for the first time. These are supplemented by an exemplary account of the partnership work between the dioceses of Mainz and Erfurt.