This proposed Austrian Crystallographic Diffraction Consortium (ACDC) BAG is to support various macromolecular structural biology groups across Austria (totally 15 research groups at 8 institutions in 5 cities). We employ mainly the technique of X-ray crystallography to characterize macromolecular biological complexes. Approval of this BAG will be absolutely essential for researchers in all these groups to carry out their structural studies on various health-related subjects, 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.