Polystyrene latexes were synthesized via living free-radical chemistry with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) in both alcoholic and aqueous alcoholic media using poly(N-vinylpyrrolidone) (PVP) as a steric stabilizer at 112-130 degrees C. Genuine dispersion polymerization was only achieved in ethylene glycol or ethylene glycol-water mixtures. In the absence of TEMPO, near-quantitative monomer conversions, high molecular weights, broad molecular weight distributions, and submicrometer-sized latexes were obtained. The addition of TEMPO had a profound effect on the polymerization chemistry : only moderate monomer conversions las low as 20%, with a maximum conversion of 60% obtained after 71 h) and larger, typically micrometer-sized, latexes were obtained with TEMPO-mediated syntheses. Polydispersities (M-w/M-n＇s) as low as 1.11 were achieved in the presence of TEMPO, but only relatively low molecular weight polystyrene chains were obtained. All TEMPO-synthesized latexes had spherical particle morphologies and very broad size distributions, as evidenced by scanning electron microscopy (SEM) and disk centrifuge photosedimentometry (DCP), respectively. Surprisingly, high Gamma values were calculated for the adsorbed PVP stabilizer, which suggests that it is not located exclusively on the outside of the polystyrene latex particles.