An aerosol delivery system has a fluid transfer article with a first region for holding an aerosol precursor and a second region in the form of a flexible diaphragm to which the aerosol precursor is transferred from the first region. The second region includes an activation surface which interacts thermally with a heater of the aerosol delivery system to form an aerosol from said aerosol precursor. When the user sucks or inhales through the aerosol delivery system, the diaphragm flexes to open an air-flow pathway between the activation surface and the heater, so that aerosol passes from the heater to the user in the air-flow. When the user ceases to suck or inhale, the flexible diaphragm flexes to close the air-flow pathway and reduce escape of aerosol precursor from the second part of the fluid transfer article.
