The research infrastructure group indexes analogue and digital archival holdings and makes them accessible online. The core is formed by the Scientific Collections for the History of Building and Planning in the GDR, which, as a special archive for the recent history of spatial development in East Germany, are available to international research as well as to the general public. The core tasks of critically reflecting on the collection, preservation and accessibility of holdings are supplemented by a variety of educational activities. These include online offerings and exhibitions as well as strategic networking with other archives and collaborative projects within the Leibniz Association. Since the beginning of 2020, services are digitally expanded as part of a special budget project, databases will be merged in a dedicated portal and the holdings connected to archival portals. The infrastructure group takes up current approaches of the digital humanities, such as the visual indexing of holdings, the evaluation of mass data, methods of geocoding and mapping as well as the involvement of laypersons in the indexing of materials (citizen science). In this way, it links archival development, digitization and research in a contemporary way.