This e-book gathers the extended and updated versions of 8 papers selected among 58 from the IMS 2004 international conference, which was held in Troyes, France, in July 2004. They introduce some original approaches and new results that thrust to a real-world predictive maintenance application. This e-book also aims at promoting the development of intelligent and efficient maintenance systems, to reach failure risks closer to zero. The selected papers offer methods enabling a satisfactory operational availability of machineries, through the monitoring, the diagnosis, the forecasting and the decision support to predictive maintenance actions.