NMR spin-spin solvent relaxation measurements have been performed on a series of aqueous dispersions of silica with physisorbed poly(ethylene oxide) (PEO) and poly(vinyl pyrrolidone) (PVP). Enhancements in the specific relaxation rate constant as a result of polymer adsorption were observed. Measurements of the relaxation rate constant as a function of the concentrations of silica and polymer in the system have been used to determine the amount of polymer trains adsorbed at the particle surface, at saturation. Studies of PEO-PVP-silica dispersions have shown that preadsorbed PEO is completely displaced when the silica concentration is small enough to allow the added PVP to saturate the surface. When the concentration of silica is increased beyond this point, then PEO and PVP are able to coexist on the particle surface.