A dispenser comprises a reservoir 10 containing fluid 12 and an outlet 14 at a base of the reservoir which leads to a dispensing port 18 comprising a piezo element 20. The preferably porous piezo element vibrates to dispense fluid from the dispensing port. A bleed tube 32 having a closable valve 36 is also provided, wherein the bleed tube communicates with one end of the dispensing port and extends upwardly above the port to expel air. The dispenser further comprises means, such as a syringe 24, for providing below-atmospheric pressure to the portion of the reservoir above the fluid. An openable cover (104, Fig 2) may be present to conceal part of the dispenser, whereby the piston and/or valve may be connected to the cover so as to impose below-atmospheric pressure and/or to close the valve when the cover is shut. Refills (108, Fig. 6) for the dispenser are also disclosed.