The authors present the accepted strategy of Partial Deafness Treatment (PDT) based on long-term observation and results: 8-years long in adult patients and over 5-years long in children. In therapy, there are two fundamental modes of complementary stimulation in cases of moderate to severe hearing loss. One of them is the acoustic stimulation (AS), comprising patients who use amplification with hearing aid (HA) and/or middle ear implant (MEI). The other mode, presented by the authors in this study, is the electric stimulation using cochlear implant (PDCI). The entire material in this mode is divided into three groups: 1. Electrical Complement (EC); 2. Electric Acoustic Stimulation (EAS); and 3. Electric Stimulation (ES). Surgical approach in PDT is based on the 6-steps method, emphasizing round window approach to the scala tympani. The results obtained in the long-term follow-up shows the preservation of preoperative hearing in 97% of subjects. Overall, for all audiometric frequencies the differences in mean pre- and mean postoperative thresholds, measured before surgery and 3 months afterwards were not statistically significant (p>0.05). In all four groups we observed a significant increase in scores between pre-operative and 12 months after surgery both under quiet and noisy conditions. The presented concept, supported by the substantial material and long-term follow-up, allows the comprehensive approach to the treatment of partial deafness using different modes of stimulation.