A cleaner head for a vacuum cleaner has a rotating brush bar driven by an air-cooled motor, which is mounted inside the cleaner head with at least a section of the motor being located inside the brush bar. To cool the motor in use, an external casing of the motor is provided a plurality of air-cooling holes comprising at least one air intake and at least one air exhaust. These cooling holes are connected—intake to exhaust—to form one or more air-cooling paths through the inside of the motor. Each air intake is connected to an upstream clean air inlet by a stationary—not rotating—intake duct, and each air exhaust is similarly connected to a downstream clean air outlet by a stationary—not rotating—exhaust duct. This avoids the problems associated with using the rotating brush bar itself as a duct for carrying cooling air to the motor.