This proposal is about the development of sustainable detergency based formulations, based on the blending of biosurfactants and conventional surfactants, and is part of a CASE project funded by EPSRC and Unilever. The focus of the project is to improve our understanding of the interfacial and solution properties of complex multi-component mixtures of biosurfactants and conventional surfactants, and relate those properties to the conditions for optimal performance. We request SANS beam time on SANS2D to progress this project and specifically to study the self-assembly of a 3 component nonionic /anionic surfactant mixture and a 5 component surfactant mixture of the rhamnolipid biosurfactant with that nonionic / anionic surfactant mixture