This paper describes the modelling and comparison of piezoactive composites of 0-3 and 3-3 geometry. Algorithms for the evaluation of effective elastic, piezoelectric and dielectric constants are proposed which can be used for the prediction of piezoelectric sensitivity and optimisation of properties. The hydrostatic piezoelectric voltage coefficient g(h), figure of merit d(33).g(33) and hydrostatic figure of merit d(h).g(h), are calculated for PbTiO3 based piezocomposites in which the anisotropy factor -d(33)/d(31) of the piezoelectric phase can be varied from small to infinitely large values. Maxima of these parameters are determined and factors influencing piezoelectric sensitivity of the composites are analysed. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.