New cinnamic acid type nonlinear-optical (NLO) photopolymers and their use in frequency doubling Cerenkov waveguides are reported. Cerenkov configurations are shown to be particularly appropriate for efficient second-harmonic generation in NLO polymers. Analysis of Cerenkov waveguides in three-layer configurations allows optimization of their performance with respect to polymer layer thickness and substrate parameters. The NLO efficiencies predicted from the model and from independently determined NLO material parameters are qualitatively in agreement with the experimentally observed large Cerenkov NLO efficiency of 0.2&percent; W−1 cm−1. We show further that improved device performance results from novel four-layer waveguide configurations. ©1997 American Institute of Physics.