In high energy accelerators as LHC energy stored in the beams is orders of magnitude above the damage level of accelerator components like magnets. Uncontrolled release of energy can lead to a serious damage of equipment and long machine downtimes. In order to cope with these potential risks Protection Systems were developed at CERN including two software systems: MCS (Management of Critical Settings) and RBAC (Role Based Access Control). RBAC provides means for authentication and an authorization facility which grants access to the critical parts of a control system. Second layer of security is provided by MCS by ensuring that critical parameters are coherent within the software and hardware components of a control system and can only be changed by an authorized person. MCS system is aimed for the most critical and potentially dangerous equipment (e.g. Beam Loss Monitors) and is complementary to RBAC infrastructure. Both systems are fully integrated in the control system for LHC and SPS and were successfully commissioned for the first beam in LHC. This presentation will describe the MCS architecture, current status and its operational deployment together with plans for the future.