Implantable hearing aids are not only gaining importance for the treatment of sensorineural hearing loss, but also for treatment of mixed hearing loss. The most frequently used active middle ear implant is the Vibrant Soundbridge (VSB) system (Fa. MED-EL, Innsbruck, A-sterrreich). Following widening of the spectrum of indications for the VBS, various new coupling systems have been established. Based on the literature, available petrosal bone investigations and finite element model (FEM) calculations, this article summarizes the current knowledge concerning mechanical excitation by the VSB. Important concomitant aspects related to coupling, transmission and measurement are also discussed.