An aerosol provision system for generating aerosol from a removable consumable comprising an aerosol forming material, comprising: an aerosol provision device comprising: a housing having an opening in one end; a power source; a receptacle; a sensor; an aerosol generating element; wherein the sensor and the aerosol generating element are configured to operate in response to power received from the power source; and a removable consumable for engagement with the receptacle, wherein the removable consumable is insertable into the opening so that it is received within and engaged with the receptacle and wherein an end of the removable consumable projects out of the aerosol provision device through the opening when the removable consumable is engaged with the receptacle, such that a user may inhale the aerosol through the removable consumable in use, the removable consumable comprising: aerosol forming material; and a marker; wherein the aerosol generating element is configured to aerosolise the aerosol forming material and the sensor is configured to detect the marker when the removable consumable is engaged with the receptacle; wherein the removable consumable defines an outer profile having at least a first alignment feature and the receptacle defines an inner profile comprising at least a second alignment feature corresponding to the first alignment feature; and wherein the first and second alignment features are configured to restrict the orientation of the removable consumable to a single orientation when engaged with the receptacle such that the aerosol forming material is aligned with the aerosol generating element and the marker is aligned with the sensor. an aerosol provision device comprising: a housing having an opening in one end; a power source; a receptacle; a sensor; an aerosol generating element; wherein the sensor and the aerosol generating element are configured to operate in response to power received from the power source; and a housing having an opening in one end; a power source; a receptacle; a sensor; an aerosol generating element; wherein the sensor and the aerosol generating element are configured to operate in response to power received from the power source; and a removable consumable for engagement with the receptacle, wherein the removable consumable is insertable into the opening so that it is received within and engaged with the receptacle and wherein an end of the removable consumable projects out of the aerosol provision device through the opening when the removable consumable is engaged with the receptacle, such that a user may inhale the aerosol through the removable consumable in use, the removable consumable comprising: aerosol forming material; and a marker; aerosol forming material; and a marker; wherein the aerosol generating element is configured to aerosolise the aerosol forming material and the sensor is configured to detect the marker when the removable consumable is engaged with the receptacle; wherein the removable consumable defines an outer profile having at least a first alignment feature and the receptacle defines an inner profile comprising at least a second alignment feature corresponding to the first alignment feature; and wherein the first and second alignment features are configured to restrict the orientation of the removable consumable to a single orientation when engaged with the receptacle such that the aerosol forming material is aligned with the aerosol generating element and the marker is aligned with the sensor.