Objective: Children with isolated hearing impairment who have received cochlear implant at the optimal age mostly achieve remarkable results that are assessed by objective speech perception and production measurements. Different outcomes may be expected in case of conditions which may have a negative impact on postoperative performance. The aim of this study was to assess the influence of potentially limiting factors on postimplant outcomes. Methods: Four groups of examinees (11 in total) were involved by the study: (A) four children with additional disabilities, (B) three children with cochlear malformation and/or ossification, (C) three reimplanted children, (D) a child with retrocochlear (cochlear nerve) pathology. Hearing, speech perception and production were examined by pure tone audiogram, speech audiogram, categories of auditory performance, speech intelligibility rating, listening progress profile, and monosyllabic trochee polysyllable test. Postoperative positive life changes were assessed by a questionnaire. Results: Group A: perception skills better than expected, less satisfactory speech development. Group B: good sound perception, poor understanding. Group C: after reimplantation undisturbed conditions for continuation of optimal rehabilitation course. Group D: unsatisfactory results of pure tone hearing as well as speech perception and production. Conclusion: In spite of unfavourable conditions all examinees, except a child with retrocochlear pathology, were found to have a considerable benefit after cochlear implantation (with regard to obvious heterogeneity within each group). Evaluation of success, especially in children with multiple handicaps, also has to include subjective indicators of positive life changes, even those not directly associated with hearing. Previous article in issue