A partially implantable vestibular prosthesis system is described which includes an external movement sensor that is attachable to the outer skin surface of a patient's head for generating an external movement signal which represents movement of the patient's head. An external transmitter is in communication with the external movement sensor and provides an electromagnetic transmission of an implant communication signal which includes a signal component based on the external movement signal and an electrical power component that provides electrical power for implanted system components. An internal movement sensor is implantable under the skin of the patient's head for generating an internal movement signal which represents movement of the patient's head. And an implant processor also is implantable under the skin and in communication with the internal movement sensor and the external transmitter for generating an implant stimulation signal based on one of the movement signals to electrically stimulate target neural tissue for vestibular sensation by the patient.