ß-barrel outer membrane proteins are implicated in a broad range of functions crucial for their survival. Such functions include passive nutrient uptake, active transport of large molecules, protein secretion as well as adhesion to host cells, through which bacteria expose their virulence activity. These proteins differ from typical membrane proteins (like the ones found in inner membranes) in that their membrane-spanning regions are formed by amphipathic beta strands instead of alpha helices. Their biological importance together with the inadequate annotation and classification found in public databases, urges the need for intensive studies and accurate data collection regarding ß-barrel proteins.