High cost pressure in merchant shipping and increasing availability requirements on the part of charterers require reliable maintenance of ships and their systems. This challenge can be met with optimized maintenance planning and more efficient maintenance processes. At present, time-based, preventive maintenance processes are predominantly carried out. Condition-based maintenance has so far mainly been used for ship propulsion. Significant potential cost savings could be realized in maintenance and spare parts procurement. To this end, the CML has developed a methodology for condition-based maintenance (CBM) of other ship systems.