Nitrile/vinyl ether-containing polymers for photoresist compositions and microlithography methods employing the photoresist compositions are described. These photoresist compositions comprise 1) at least one ethylenically unsaturated compound comprised of a vinyl ether and 2) a nitrile-containing compound, e.g., acrylonitrile, which together impart high ultraviolet (UV) transparency and developability in basic media. In some embodiments, these photoresist compositions further comprise a fluoroalcohol group. The photoresist compositions of this invention have, high UV transparency, particularly at short wavelengths, e.g., 157 nm and 193 nm, which property makes them useful for lithography at these short wavelengths.