A delivery device, e.g. an inhaler, comprises a rotatable metering member adapted to dispense a measured amount of material, a material delivery passage and a material delivery orifice and at least one actuator member adapted to move the metering member form a material retaining position to a material dispensing position. In a magazine comprising a plurality of metering members, the actuator and metering members may operate in a radial direction. A plurality of rotatable magazines may be utilized in the delivery device. The delivery device may be used to deliver a single or a combination therapy.