A delivery device for and method of delivering a substance, the delivery device having an outlet member through which substance is in use delivered in an entraining gas flow, and a substance supply unit for supplying substance to be entrained by an entraining gas flow as one or both of a vapor or a fine aerosol mist, wherein the substance supply unit has a flow channel which is fluidly connected to the outlet member, and a substance supporting element for supporting substance, at least a surface of which is in use disposed in the flow channel.
