Today biosurfactants are defined mainly as chemically produced products from renewable resources. They are used as surfactants or emulsifiers in the textile industry, in household cleaners, and cosmetics. Despite their structural diversity, so far biosurfactants produced by microorganisms are only found in few products. As part of the project BioSurf the Fraunhofer IGB with its project partners is developing surfactants from microorganisms as well as enzymatically produced surfactants based on renewable resources. The Fraunhofer IGB is focussing on optimizing smut fungi (Ustilago maydis, Pseudozyma ssp.) to produce the glycolipids cellobiose lipid and mannosylerythritol lipid. By process improvement and the corresponding product preparation, biosurfactants will be economically manufactured and thus will be able to compete with conventional surfactants.