[en] This report arises from the sixth series of peer discussions on regulatory practices entitled 'Regulation of Life Cycle of Nuclear Installations'. Senior regulators from 18 Member States participated in three peer group discussions during 1997-1998. This report presents the outcome of these meetings and recommendations of good practices identified by senior regulators, which do not necessarily reflect those of the governments of the nominating Member States, the nominating organizations, or the IAEA. The purpose of this report is to disseminate the views which the senior regulators presented at the meetings relating to the policies, principles and requirements imposed by regulatory bodies for the safe management of the life cycle of a nuclear installation. The intention of doing this is to assist Member States in the formulation and enhancement of their regulatory control over PLCM by identifying commonly accepted good practices. This report is structured to cover the subject matter under the following main headings: Policies and Principles for the Life Cycle Management of Nuclear Installations; Responsibilities of the Regulatory Body and the Operating Organization; Requirements and Criteria Imposed by the Regulatory Body; Licensing and Regulatory Assessment for Plant Life Cycle Management; and Good Practices