An aerosol delivery system has a fluid-transfer article that has a first region for holding an aerosol precursor and a second region 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. At least a part of the heater is deformable, in response to a temperature change between a first and a second temperature. When at the second temperature, which normally is higher than the first temperature, the deformable part of the heater is spaced from the activation surface to define an air-flow pathway between the heater and activation surface, through which air can flow to transfer the aerosol to the user. At the first temperature, the deformable part of the heater moves into contact with the activation surface, to obstruct the air-flow pathway and reduces escape of aerosol precursor from the second part of the fluid-transfer article.
