Abstract: A method and apparatus for delivering aromatic substances for olfactory stimulation, treatment and/or therapy which includes a delivery assembly including a chamber into which air is introduced and subsequently delivered under even pressure through a mixing venturi. A plurality of conveying conduits are selectively communicated with the venturi so that aromatic substances are entrained in the air passing through the venturi to a discharge mask or zone. The conduits communicate with a plurality of containers of aromatic liquids, solids, and semi-solids. The containers are subject to selective introduction of pressurized air by way of a plurality of valves. A system is provided for controlling the operation of the valves to thereby control the substances discharged from the apparatus.