Tinnitus is defined as the perception of sound in the absence of any appropriate external stimulation. It is a common, bothersome and hard-to-evaluate symptom and in most cases it cannot be objectified. Its incidence in Germany and the western world is about 10%. About 1-2% of the population are severely disturbed by tinnitus and it may disrupt everyday activities and sleep. Recent theoretical developments favour a neurophysiological approach as an explanation for tinnitus in addition to a psychoacoustic model based on peripheral lesion in the cochlea or auditory nerve. In the neurophysiological model, the processing of the tinnitus signal plays a dominant role in its detection, perception and evaluation. Therefore, attention and other psychological factors become important in the understanding and treatment of tinnitus. Many treatments of chronic tinnitus have been proposed and implemented. Today, cognitive-behavioural treatment is regarded as an important part of an integrative therapy which may be compiled of counselling, relaxation therapy, instrumental (hearing aid, tinnitus masker, tinnitus instrument, tinnitus noiser) and pharmacological tools (lidocaine, neurotransmitters). In well-controlled studies the empirical support for other therapeutical approaches such as acupuncture is weak. This work gives a review of the current knowledge of the etiology, pathogenesis, epidemiology, the interdisciplinary diagnostic approach and treatment of tinnitus and especially focuses on insurance and medico-legal aspects.