The invention relates to a method for operating at least a first wind turbine including the steps of: recording a tower oscillation, initiating a measure to reduce oscillation if the tower oscillation is or contains a longitudinal oscillation, and if the amplitude of the longitudinal oscillation exceeds a predefined threshold value, and the measure for reducing the oscillation comprises freezing the current pitch angle at the current value for a predefined freezing period, switching the pitch control algorithm used, in particular in such a way that the control speed is reduced, adjusting the yaw position by a predefined yaw angle, switching the operation of the first wind turbine from a first operating mode based on a first power curve to a second operating mode based on a second power curve, and/or if, with regard to the current wind direction, the first wind turbine in a wind park is located behind a second wind turbine, adjusting the rotational speed of the first wind turbine to the rotational speed of the second wind turbine in such a way that the rotational speed of the first wind turbine differs from the rotational speed of the second wind turbine by at least a predefined differential rotational speed.