The CERN accelerator controls infrastructure spans over several machines and several thousands of devices are used to collect and transmit piece of control data. Each of these remote devices might fail and therefore prevent correct operation. A complete diagnostic and monitoring infrastructure has been developed in order to provide Operation crews with complete and easy to use graphical interface presenting the state of the controls system. Simple agents running in each surveyed item periodically report monitoring information to a central server. Graphical JAVA clients in the operation centers subscribe to this monitoring data and display a view of the current state of the machines. Mouse actions from these clients allows for diagnostic commands to be sent to the agent to get additional details or to repair a faulty situation. This presentation will describe the overall architecture of DIAMON, present the different agents running in the controls system and a few views of the graphical clients. The outcome of the first months in operation of the DIAMON tools will also be presented. Finally, the future plans will be exposed.