The ferroelectric properties of unoriented films of a random copolymer of vinylidene fluoride with trifluoroethylene (73/27 mol %) as a function of plasticizer concentration, tricresyl phosphate (TCP), were examined. The percentages of dopant chosen were 5% and 10% by weight and a comparison was made with undoped films. The mechanical and thermal properties of these films were examined both before and after poling. Electric field poling induced the all-trans chains of the ferroelectric phase to pack in a more compact crystal structure, and also produced an increase of 7 degrees C in the Curie transition temperature (T-c). The results of piezoelectric coefficient measurements (d(31) and e(31)), X-ray diffraction analysis, and DSC thermal investigations provided insights into the ferroelectric nature of these plasticized copolymer films. In the films with 5% dopant, the crystallinity and remanent polarization decreased by 15% and 50%, respectively, when compared to the undoped films, yet showed a 21% increase in piezoelectric coefficient, d(31). Contrary to this behavior, films doped at 10% TCP, with approximate to 55% crystallinity, indicated almost no remanent polarization.