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Addressed is the importance of prognostics and health monitoring to the cost of operations where a few percent degradation in operating efficiency can have a major impact. The high stress levels typical of the gas turbine imply relatively small margins of safety with potentially catastrophic consequences. Operations and maintenance techniques employ utilization profiles to optimize shop visit rates and minimize the exposure to unscheduled events as a result of such things as low cycle fatigue, thermally induced damage, blade erosion and/or Foreign Object Damage (FOD). The concepts of Mean Time Between Failure (MTBF), Mean Time To Repair (MTTR) and Mean Delay Time (MDT) are examined in detail together with the Failure Modes, Effects and Critically Analysis (FMECA) which is a key design tool for the establishment of specific maintenance regimens. The effects of power level and power cycling on life consumption as a design parameter are explored. Failure mode analysis, fault diagnosis and the diagnostic algorithm are discussed relative to operations and maintenance support. The availability of the on-board microprocessor-base data collection device, particularly on more recent applications has lead to the move towards condition-based operations and maintenance. This facility allows real time data transmission via the Aircraft Communication and Reporting System (ACARS) from the aircraft to the operator's maintenance center.