PZT ferroelectric capacitors are commonly fabricated using Pt electrodes. Crystallization in an oxygen ambient of sol-gel deposited PZT films is influenced by the nature of the adhesion layer used for the Pt electrode. Here we report results of the TEM investigation of the microstructures of PZT crystallized on Pt/Ti and Pt/TiO2 substrates. PZT films on either substrate show a two-phase microstructure consisting of larger perovskite grains and finegrained (<3nm) pyrochlore matrix. The perovskite grains are dense, free of any porosity and HRTEM shows the observed domains to be 90° <101> twins. EDS spectra detect a lower Pb/Ti ratio for the pyrochlore matrix compared to the perovskite grains. Differences between the two substrates consist of the perovskite to pyrochlore ratio and more importantly the perovskite grain size.