A dispenser capable of dispensing a fluid via a vertically-oriented piezo device comprises a reservoir in the form of a replaceable cartridge containing a fluid to be dispensed, a planar piezo element having front and rear surfaces and which in use is oriented with its plane vertical and which is drivable to vibrate and thereby dispense fluid from the front surface, and a pump to draw a predetermined amount, or dose, of fluid from the reservoir and to drive the dose of fluid at a predetermined above-atmospheric pressure to the rear surface of the piezo element for dispensing.
