A humidifier includes a base defining a reservoir for retaining liquid, a humidification device for inducing dispersion of liquid withdrawn from the reservoir into the environment and a liquid storage tank having an outlet for feeding liquid into the reservoir. The humidification device includes a heated disc for evaporating a stream of liquid delivered from the reservoir to the heated disc by a delivery mechanism. The delivery mechanism may deliver the stream of liquid as a mist, a thin film or a controlled stream of liquid onto the disc.