For many complex capital goods, the cost of maintenance represent a large fraction of the Total Cost of Ownership (TCO). These maintenance costs are often much larger than the procurement cost (AberdeenGroup 2003). Therefore, it is essential that asset owners develop strategies that minimize these cost whilst maximizing the uptime and safety. Another issue of maintenance is that the most one-off build assets are designed according to specific needs. As a result, there is not much failure data available at the OEM’s. This also explains why maintenance plans are often developed and performed by the company itself or by contractors, instead of the OEM’s. These characteristics ask for a dynamic maintenance strategy. That strategy needs to adapt to the increasing availability of data during the life-time. Whereas preventive maintenance may be appropriate at the start, other types of maintenance may later become preferable as more information becomes available. Later (when decisions could be based on available data) that dynamic policy should lead to reduced downtime.