H-1 NMR solvent relaxation has been used to probe the effect of SDS on the adsorption of poly(ethylene oxide) at the silica-water interface. In the absence of SDS an enhancement in the water relaxation rate resulting from the adsorption of PEO was observed while for PEO in the absence of particles only a negligible enhancement was observed. However, upon addition of SDS to the PEO/silica system a sequential reduction in the relaxation rate with increasing SDS was found. The results are discussed in terms of the levels of adsorbed polymer and its conformation at the intel face.