The BAG includes groups situated at four Flemish universities: Antwerp, Brussels, Ghent and Leuven. Several of these groups are part of the elite Flemish Institute of Biotechnology (VIB). The proposed projects are highly diverse, including viral, prokaryotic and eukaryotic proteins with a strong focus on targets and processes of biomedical relevance. Many projects deal with membrane proteins, cell surface receptors and protein-protein complexes. Central to the research in the BAG associated groups is the employment of integrative methods in structural biology combining X-ray crystallography, SAXS, and cryo-electron microscopy. Many crystals in the various proposed projects are small in size and radiation sensitive, requiring the use of the high brilliance MX beam lines, preferably with micro-focused X-rays. This is a continuation of a previous Belgian BAG which has resulted in numerous top-tier publications.