Changes in the quality of life perceived by patients over a 24-month period were examined by means of three questionnaires: the Patient Quality of Life Form, the Index Relative Questionnaire Form, and the Performance Inventory for Profound Hearing Loss Answer Form. In addition, the relationships among the three questionnaires were examined as a function of age, length of deafness, and a battery of selected audiological tests. The results of the study indicate that a cochlear implant makes significant, positive changes in the quality of life of patients and in their ability to communicate. The patients and their relatives differ somewhat in their perceptions of these changes. The degree of improvement in quality of life perceived by a patient as the result of an implant is a function of the years of deafness. In general, the longer an individual has been deaf, the less improvement in quality of life that is perceived.