Abstract: A multi-DOF piezoelectric actuator that may be constructed with sizes of about or less than one millimetre. The multi-DOF piezoelectric actuator is capable of generating motion of a rotor element or slider element, about or in, each of the three fundamental axes of three dimensional space. The actuator can comprise a piezoelectric element (10) having one or more sidefaces, a first endface, and a second endface, wherein at least one or more sidefaces comprise a plurality of separate sideface electrodes (11) and at least one of the first or second endfaces comprise an endface electrode (12). A transducer element (30,40) and isolation structure (5) for use in a piezoelectric actuator are also described.