Recent advancements in wind turbine condition monitoring and fault diagnosis have focused on gearbox and bearing, rotor and blades, generator and power electronics, and overall turbine system diagnosis. Key trends include the use of time-frequency analysis tools like wavelets, acoustic emission for detecting early failures, and model-based reasoning algorithms for cost-effective fault detection. The impact of wind load on diagnostic accuracy has been noted, and separating wind load from monitoring decisions can reduce downtime costs.