Polymer-stabilized latex dispersions find many applications but our understanding of such suspensions is limited; data on well-characterized systems can furnish needed insight. To provide this information, the behavior of bare particles and particles coated with adsorbed poly(ethylene oxide) was investigated using electrophoretic mobility and photon correlation spectroscopy measurements. Bare particles show the typical maximum in mobility as a function of salt concentration; adsorbed neutral polymer reduces the mobility and suppresses the features. Hydrodynamic size measurements indicate that the polymer layers are rather thick and almost completely occlude the diffuse charge. Nevertheless, the particles retain a significant electrophoretic mobility, indicating that the electrokinetic shear plane is located somewhere inside the polymer layer. Comparing experimental results with those fi om an approximate theory for fuzzy particles indicates that the layer's principal effect is hydrodynamic.