Products such as fabric and hair conditioners are commonly in the form of di-alkyl chain cationic lamellar phase dispersion. The effects of shear on such lamellar phase dispersions play an important role in formulation, processing and use. The structure and rigidity of such dispersions are frequently controlled by the addition of cosurfactants or additives such as perfumes or alcohols, but the membranes remain relatively rigid. This proposal focuses on the impact of unsaturation of the alkyl chains on the lamellar phase microstructure and the impact of flow on that microstructure. SANS beam time is requested to probe the effects of Couette shear flow and elongational flow on the lamellar dispersion of an unsaturated di-alkyl chain cationic surfactant, and due to an increase in membrane flexibility a rich pattern of behaviour is expected.