The application of chiral perturbation theory to low energy processes of abnormal intrinsic parity (anomalous) is discussed. The full infinite part at next-to-leading order is calculated. Estimates of the finite part of the effective Lagrangian from vector meson dominance and the chiral constituent quark model are obtained. This is then applied to decays of pseudoscalars to photon–photon and photon–three-pseudoscalar couplings.