A reference electrode for an inner ear stimulation device is disclosed. The reference electrode is to be implanted and includes a protruding conductor portion and an insulated conducting portion connected to a lead for connection to the device. The protruding conductor portion is shaped so as to present a generally smooth surface without any substantial projections to impede removal in the event that the electrode is withdrawn in the direction of the lead. The smooth profile and lack of an undercut assist in preventing biofilm accumulation and growth. This reduces the risk of post-surgical complications such as infection.
