Key source material for research on the history of the SBZ/GDR and its political elites are the Minutes of the Central Secretariat of the SED and the Politbureau of the Central Committee of the SED from 1946 to 1989, published completely for the first time in Part 3 of this series. The Central Secretariat and, from 1949, the Politbureau of the ZK of the SED were the political nerve centres of the evolving GDR and later fully established state. Both committees were not only responsible for all the important political decisions, but had considerable influence on the economic, social and cultural life of the SBZ and DDR. The protocols of and excerpts from resolutions, submittals and attachments from the meetings of both these political establishments published here provide unique evidence about the development of the GDR from the post-war period to the fall of the Berlin wall.