The equilibrium constants and enthalpies describing self-association and interassociation between functional groups in blends of poly(hydroxy ether of Bisphenol A) [phenoxy (PH)] and poly(vinylpyrrolidone) (PVPr) have been employed in an attempt to explain different experimental results of these blends. The methodology of an association model developed by Painter, Coleman, and their coworkers has been used. The simulated glass transition temperatures and enthalpies of mixing agree with experimental results. The same set of association constants and enthalpies reproduces the free carbonyl fraction in a related mixture, epoxy resin/poly(vinylpyrrolidone). Finally, the model gives a reasonable approach to the influence of the hydroxyl groups of phenoxy in its miscibility with PVPr, when these hydroxyl groups are progressively eliminated from the PH molecule by benzoylation.