An improvement in the cyanoethylation process using a bed of basic ion exchange resin catalyst wherein the conversion of the acrylonitrile is limited to the range between from about 60% to about 96%. A monoadduct intermediate can be recycled. As a result of the limitation to the conversion selectivity as to the desired product is in excess of 95%. The improved process, e.g., has a selectivity of 98% when the conversion is about 82% and the reactants are acrylonitrile and ethylene glycol.