Cochlear implantation (CI) is a new form of treatment in the rehabilitation of single-sided deafness. The patient requires thorough initial examination and a full explanation of alternative treatment options prior to determining the indication for CI treatment. To date, we have treated 28 patients with CI, of whom data are available for 11 after 12 months. We examined speech comprehension in background noise and localisation ability 12 months after CI implantation compared to conventional CROS (contralateral routing of signal) hearing aids, BAHA (bone-anchored hearing aid) and hearing in untreated patients. In addition, we determined the subjective handicap (HHIE, hearing handicap inventory for the elderly) and the subjective success (IOI-HA, international outcome inventory for hearing aids; SSQ, spatial and qualities of hearing scale) of each treatment option. After 12 months' experience, the results show a significantly better localisation ability and an improvement in speech comprehension in background noise with CI than with the other treatment options. Subjective results also show a clear benefit with CI. Careful patient selection is a decisive factor for successful treatment of this patient group. Under these conditions, CI is a treatment option with which significant improvement in speech comprehension and localization ability in single-sided deafness is possible.