A process where-by "The important functions (of a piece of equipment) are preserved with routine maintenance that are identified, their dominant failure modes and causes determined and the consequences of failure ascertained. Levels of criticality are assigned to the consequences of failure. Some functions are not critical and are left to "run to failure" while other functions must be preserved at all cost. Maintenance tasks are selected that address the dominant failure causes. This process directly addresses maintenance preventable failures. Failures caused by unlikely events, non-predictable acts of nature, etc. will usually receive no action provided their risk (combination of severity and frequency) is trivial (or at least tolerable). " This is referred to as 1. Operational Readiness Testing 2. Field Support 3. Scheduled Maintenance 4. Logistics Support 5. Sense and Respond Logistics 6. Reliability Centered Maintenance