A medicament delivery device comprising: - a tubular housing (120,130), having a proximal end and an opposite distal end; - an actuator member movably arranged in relation to said tubular housing (120,130) for triggering a medicament delivery; - a medicament container arranged within the tubular housing and having a delivery member protruding through the proximal end of the tubular housing; - a cap releasably connected to the proximal end of the tubular housing (120,130) and covering the delivery member characterized in that the device further comprises interlocking means arranged to interact with both the actuator member and the cap such that the actuator member can only be manually actuated when the cap is removed, and wherein the locking means is a longitudinal actuator interlocking member movably arranged within the tubular housing (120,130) and arranged to interactively co-act with both the actuator member and the cap, and wherein the actuator interlocking member and the cap are connectable to each other by a first co-acting means (503,401) and wherein the actuator interlocking member and the actuator member are connectable to each other by a second co-acting means (501,204), and wherein the longitudinal actuator interlocking member is an, axially slidable, member arranged within the tubular housing (120,130) between a locked position in which the proximal first co-acting means are connected to the corresponding first co-acting means of the cap and the distal second co-acting means are abutting to a corresponding second co-acting means of the actuator member such that the actuator member is prevented from being manually actuated, and an unlocked position in which the proximal first co-acting means are disconnected from the corresponding first co-acting means of the cap and the distal second co-acting means are abutting to a corresponding second co-acting means of the actuator member such that the actuator member is allowed to be actuated, and wherein the first co-acting means of the interlocking member comprises a partial outer thread, corresponding to an outer thread of the tubular housing (120,130) both when the interlocking member is in the locked position and in the unlocked position and wherein the corresponding first co-acting means of the cap comprises an inner thread. - a tubular housing (120,130), having a proximal end and an opposite distal end; - an actuator member movably arranged in relation to said tubular housing (120,130) for triggering a medicament delivery; - a medicament container arranged within the tubular housing and having a delivery member protruding through the proximal end of the tubular housing; - a cap releasably connected to the proximal end of the tubular housing (120,130) and covering the delivery member characterized in that the device further comprises interlocking means arranged to interact with both the actuator member and the cap such that the actuator member can only be manually actuated when the cap is removed, and wherein the locking means is a longitudinal actuator interlocking member movably arranged within the tubular housing (120,130) and arranged to interactively co-act with both the actuator member and the cap, and wherein the actuator interlocking member and the cap are connectable to each other by a first co-acting means (503,401) and wherein the actuator interlocking member and the actuator member are connectable to each other by a second co-acting means (501,204), and wherein the longitudinal actuator interlocking member is an, axially slidable, member arranged within the tubular housing (120,130) between a locked position in which the proximal first co-acting means are connected to the corresponding first co-acting means of the cap and the distal second co-acting means are abutting to a corresponding second co-acting means of the actuator member such that the actuator member is prevented from being manually actuated, and an unlocked position in which the proximal first co-acting means are disconnected from the corresponding first co-acting means of the cap and the distal second co-acting means are abutting to a corresponding second co-acting means of the actuator member such that the actuator member is allowed to be actuated, and wherein the first co-acting means of the interlocking member comprises a partial outer thread, corresponding to an outer thread of the tubular housing (120,130) both when the interlocking member is in the locked position and in the unlocked position and wherein the corresponding first co-acting means of the cap comprises an inner thread.