Surfactant self-assembly is an important phenomenon in a wide range of processes and applications. SANS has played a central and key role in developing our understanding of surfactant self-assembly. From the early 1980’s D11 has been the leading and pioneering SANS instrument for such studies. Three key issues from some the early studies on D11, associated with micelle models, the complementarity of SANS and neutron spin echo, and the application of shear alignment, and which are still relevant and important to current studies, will be revisited. The contribution of more recent studies of mixed surfactant self-assembly will be reviewed, with a particular emphasis on three aspects: the role of surfactant molecular structure in manipulating the micelle structure, the complex evolution of structures that can arise in mixtures, and the emerging importance of biosurfactants.