Abstract: A method and system for monitoring the operation of a wind energy installation. State data relating to the wind energy installation is recorded and discrepancies are found between the state data and an associated comparison value. A failure probability of the wind energy installation is determined based on any found discrepancy. An availability value for the wind energy installation is determined from the ratio of the actually produced amount of electrical energy to the total amount of energy which can potentially be produced. The availability value and the failure probability are then combined to form a repair priority, which is associated with the wind energy installation. Accordingly, more uniform operation of wind energy installations can be achieved.