The Austrian Crystallographic Diffraction Consortium (ACDC) BAG aims at supporting several macromolecular structural biology groups across Austria (in total 20 research groups at 9 institutions in 4 cities). We employ mainly the technique of X-ray crystallography to characterize macromolecular biological complexes, but also solution scattering approaches are frequently used to characterize dynamic assemblies. Approval of this BAG will be essential for researchers in all our groups to carry out their structural studies on various health-related and basic research-oriented topics, which are targeted at characterizing large molecular assemblies or proteins currently under-represented in the PDB, including membrane proteins. Corresponding high-resolution diffraction data are only obtainable through the use of synchrotron radiation sources. Thus regular synchrotron access is highly desirable to maintain a competitive advantage in our individual research fields.