A device for delivery of a medicament from a container (10) having an outlet (16) at a distal end of the container (10) and a stopper (22) for containing the medicament in the container (10) is disclosed. The device comprises a housing (110, 140), a drive element (300) arranged to move in the distal direction to cooperate with the container (10), a drive mechanism comprising a trigger component (200), the drive mechanism being arranged to hold the drive element (300) in a starting position and to move the drive element (300) in the distal direction from the starting position upon displacement of the trigger component (200) from a working position to a firing position, an interlock component (250) received in the housing (110, 140) and arranged for movement with respect to the housing (110, 140) from a first position to a second position, and at least one flexible locking member (214) arranged to cooperate with a stop face (160) associated with the housing (110, 140) to prevent displacement of the trigger component (200) to the firing position when the interlock component (250) is in the first position. Movement of the interlock component (250) towards the second position causes bending of the flexible locking member (214) away from the stop face (160) to allow displacement of the trigger component (200) to the firing position.