This European Telecommunication Standard (ETS) describes the management of the security related aspects in the GSM/DCS PLMN. The management of the relevant security services is addressed with respect to the following aspects: - Overview of the security features; - Description of the relevant management procedures; - Modeling using the object oriented paradigm. The definitions and descriptions of the security features and mechanisms are contained in the specifications of the underlying procedures and are not defined in this ETS. References to appropriate GSM/DCS specifications have been made throughout the ETS, where necessary. Issues relating to the security of management (e. g. file transfer security, database security, inter operator security, etc.) are not covered in this ETS.