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Piezoelectric response nonlinearity is approached using the Preisach description of hysteretic systems as collection of distributed bistable units. The Preisach model and its recent physical interpretation in terms of moving domain wall in a stochastically described pinning field are reviewed. It is shown that such an approach can effectively render not only the piezoelectric coefficient field dependences but also the field-response hysteresis, especially in the well-known case of linear piezoelectric field dependence (i.e., Rayleigh's law) where the bistable units are distributed homogeneously. New expressions for piezoelectric nonlinear behavior departing from the classical linear dependence are then derived using a more complex distribution and are qualitatively compared to experimental data for piezoelectric materials as varied as lead titanate, strontium bismuth titanate, and lead zirconate titanate. Finally, these expressions are shown to be adequate for the description of various piezoelectric coefficient behaviors such as: polynomial dependence on the applied field, dc field effect on nonlinear contributions, and threshold field for nonlinearity. (C) 2001 American Institute of Physics.