A surgical stapling instrument comprising an elongate shaft that includes a surgical end effector that is operably coupled thereto by an articulation joint. The surgical instrument may include a central firing beam support member that extends across the articulation joint and is coupled to the surgical end effector and the elongate shaft assembly. A longitudinally movable flexible firing beam assembly may be configured to traverse the articulation joint. The firing beam assembly may comprise a plurality of beam layers that are supported relative to each other such that at least one of the beam layers is configured to movably pass on one lateral side of the central firing beam support member and at least one other of the beam layers is configured to movably pass on another lateral side of the firing beam support m member.