Polymer-surfactant stabilised emulsion droplets are a potentially exciting route for micro-encapsulation of volatile agents (such as perfumes, flavours and many other benefit agents) in a wide range of applications in home and personal care products, foods and pharmaceuticals. Understanding the nature of the polymer-surfactant interaction at the oil-water interface is an essential prerequisite to the development of such micro-encapsulation systems, and this is the basis of a new collaborative research programme between Oxford and Unilever. We porpose here SANS measurements to probe the structure of polyelectrolyte-surfactant mixtures at the oil-water interface as an initial phase of this new project.