The Vibrant Soundbridge is a semi-implantable "direct drive" hearing system for the treatment of hearing loss. People who are unsuccessful users of acoustic hearing aids or who are dissatisfied with their hearing aids have been successfully fitted with the device. The Vibrant Soundbridge is comprised of an external audio processor and an internal vibrating ossicular prosthesis, which together convert environmental sound into a vibratory signal delivered to the inner ear. This unique middle ear implant system has, over the past 25 years, proven to be an effective solution for many types of hearing loss -mild to severe sensorineural hearing loss, as well as for conductive or mixed hearing loss. This review gives an overview of the design and development of the system, with a focus on its biomechanics, over the last 25 years.