It is the aim of the proposal is to perform small angle neutron scattering (SANS) studies combined with contrast variation to determine the size and structure of the phospholipid-stabilised microemulsions prepared using a non-polar solvent (namely a diol) and a pharmaceutically acceptable oil (here ethyl oleate). Of particular interest is the effect of the structure of the non-aqueous solvent on microemulsion formation. Due to refractive index matching it is not possible to perform these studies using light scattering. Consequently neutron studies are essential to determine the formation of microemulsions these water-free systems. The studies will inform the future development of these interesting and potential important delivery systems.