Abstract: Medical therapy apparatus comprises one or more transducers (3) for emitting radiation by means of dielectric resonance when subjected to an electrical stimulus, generating means (9) for providing the stimulus and control means (8, 10) for controlling the generating means (9) whereby radiation emitted from the transducers (3) is controlled so as to synchronise with the radiation generated in a selected diseased or injured area of a body and thereby stimulate or attenuate emissions of radiation by the body in the diseased or injured area.