A sensor guard, for protecting a sensor of a vehicle. The sensor guard comprises a blade movable to sweep through a line-of-sight of the sensor when the sensor is arranged to be protected by the sensor guard, an extension of the blade in a direction parallel to the line-of-sight when the blade sweeps through the line-of sight being greater than an extension of the blade in a direction of movement of the blade when the blade sweeps through the line-of sight; and an actuator arranged and configured to move the blade to repeatedly sweep through the line-of-sight of the sensor when the sensor is arranged to be protected by the sensor guard.