[en] This paper presents the results of a study in support of NUPLEX activities to identify the major degradation issues important to life extension of both conventionally reinforced and prestressed concrete containments for PWRs and to determine any additional measures necessary to ensure their continued leak tightness and structural integrity. The degree to which any degradation mechanism occurs depends on the site-specific construction and quality control practices, and the particular containment exposure conditions, operating environment history, and design details. The modes of deterioration are addressed relation to the factors which may either increase or decrease the likelihood of occurrence. Corrosion of the liner appears to be the major concern with containment longevity. A program to establish reliable techniques to monitor areas of the liner, generally inaccessible to direct observation, needs to be developed. The report concludes that these containments possess the attributes necessary to resist or minimize the potential deterioration processes and that whatever deterioration may occur is likely only to cause a small reduction in the inherent overpressure capacity. In addition, the currently performed inspections and tests are capable of ensuring continued safety, but additional measures may be advisable for those areas which are difficult to assess because of lack of access