An assembly for a drug delivery device, the assembly having a distal end and a proximal end, which are spaced apart in the direction of an axis, the assembly comprising - a dose member, - an actuating member, - a drive feature and - a piston rod which is configured to act on a bung of an assembled cartridge containing the drug and wherein the drive feature is provided to cause a movement of the piston rod in distal direction, wherein the assembly being arranged to operate in two distinct modes, a priming mode starting from a pre-priming state and a dispense mode operating in a post-priming state, characterized in that: - in the pre-priming state the actuating member is fixed to the dose member by first engagement means or interconnection means in any direction of movement, the interconnection means extending in a spatial direction being different from the direction of the axis, such that if the actuating member is moved in a distal direction by a user the distal movement of the actuating member causes a movement of the dose member and of the drive feature, wherein the dose member is fixed to the drive feature by second engagement means such that the movement of the dose member causes a movement of the piston rod, - in the pre-priming state by movement of the actuating member the engagement of the first engagement means or the interconnection means with at least one of the actuating member and the dose member is released or a different mechanism is started which releases the actuating member from the dose member upon which the dose member and the actuating member are disengaged, - in the post-priming state the dose member is configured to be moved by a user without causing a movement of the actuating member due to disengagement of the dose member and actuating member whereupon the dose member is movable independent from the actuating member in order to perform a set and dispense action of the drug delivery device. - a dose member, - an actuating member, - a drive feature and - a piston rod which is configured to act on a bung of an assembled cartridge containing the drug and wherein the drive feature is provided to cause a movement of the piston rod in distal direction, - in the pre-priming state the actuating member is fixed to the dose member by first engagement means or interconnection means in any direction of movement, the interconnection means extending in a spatial direction being different from the direction of the axis, such that if the actuating member is moved in a distal direction by a user the distal movement of the actuating member causes a movement of the dose member and of the drive feature, wherein the dose member is fixed to the drive feature by second engagement means such that the movement of the dose member causes a movement of the piston rod, - in the pre-priming state by movement of the actuating member the engagement of the first engagement means or the interconnection means with at least one of the actuating member and the dose member is released or a different mechanism is started which releases the actuating member from the dose member upon which the dose member and the actuating member are disengaged, - in the post-priming state the dose member is configured to be moved by a user without causing a movement of the actuating member due to disengagement of the dose member and actuating member whereupon the dose member is movable independent from the actuating member in order to perform a set and dispense action of the drug delivery device.