A pulmonary delivery apparatus 10 comprising a first vaporiser 32 adapted to vaporise a quantity of a first liquid, and being characterised by a second vaporiser 34 adapted to vaporise a quantity of a second liquid, the second liquid being a different liquid to the first liquid； and an outlet 30 via which, in use, a user can inhale a mixture of the first and second vapours. Each vaporiser can each comprise a heater 35, 37 adapted to evaporate a quantity of the respective liquids, or an atomiser. The mixture can vary in increments from 100% of the first liquid and 0% of the second liquid to 0% of the first liquid and 100% of the second liquid. More than two vaporisers may be provided. The invention suitably provides for controlled and/or accurately dosed delivery of one or both of the liquids using a controller 28 which may apply a time dependent heating and cooling profile. In another aspect the device includes a first pressure sensitive switch (not shown) communicating with the outlet aperture and being adapted to detect a drop in pressure corresponding to the user inhaling on the device and a second pressure sensitive switch 39 sensing the ambient pressure. Wherein, the controller 28 is adapted to turn on the vaporiser in response to when only the first pressure sensitive switch is actuated.
