A total of eight profoundly deaf patients have been implanted with the Nucleus Limited multiple-channel cochlear prosthesis at the University of Melbourne since it became available in late 1982. All patients are everyday users of the device. Speech testing using the device alone has shown consistently high scores for a variety of closed set tests and significant levels of open set speech understanding in most of the patients. Lipreading assessment with phoneme, word, sentence and speech tracking material shows significant improvement when using the prosthesis for all patients tested. Other benefits reported are recognition of environmental sounds, decrease in tinnitus, increased confidence in social and vocational situations and improved voice control. One patient is able to cope with interactive conversations over the telephone and three others are able to use the telephone in a limited way without special codes.