Polyoxometallates (POM) are well defined transition metal clusters with a range of interesting catalytic, magnetic and optical properties. To make efficient use of these materials they are often supported on other materials to provide a high surface area open network, allowing access to the POMs. The use of solution self-assembly to structure POMs directly or evenly dispersed within a silica matrix is therefore attractive, so we are studying the synthesis and organisation of POM-headed surfactants, with C12, C14 or C16 hydrocarbon tails to incorporate them into POM-surfactant-silica films as supports. Here we propose to study the surface adsorption of POM-amphiphiles alone and in mixtures with a nonionic surfactant using contrast variation to determine the structures. Surface adsorption characterises both the mixing of these species and the interface for future silica nucleation & growth