Abstract: The present invention is a new type of high-strain, pseudo-shear mode piezoelectric ceramic actuator. The pseudo-shear mode actuator employs a stack of pre-poled rectangular ceramic sheets. The stacked sheets form a composite structure assembled from thin sheet soft PZT or PLZT which is poled in the usual direction normal to the major face of the sheet and driven by electrodes upon the major faces. The sheets are conductivity bonded at alternate ends and driven in such a way that alternate sheets expand and contract along the length dimension. Examples of uses would include actuators for linear and rotary motors; step and repeat (inchworm) type actuators; flow sensing and flow control; valving and pumping systems; active noise and vibration control; and large thin panel loudspeakers.