Disclosed a smoking substitute device comprising a body accommodating a power source, and one or more side walls projecting longitudinally from an end surface of the body. The end surface and the one or more side walls define a cavity for receipt of a vaporisable liquid reservoir and a vaporiser to vaporise the vaporisable liquid. The device further comprises an air inlet aperture formed in the one or more side walls, the aperture arranged so as to direct air that is external to the device into the cavity in a substantially transverse direction across the end surface. Also disclosed is a system comprising the smoking substitute device, a tank for storing vaporisable liquid, a vaporiser for vaporising the vaporisable liquid, the vaporiser mounted in a vaporising chamber, an airflow path extending substantially transversely from the air inlet aperture to an inlet of the vaporising chamber.
