A surgical instrument comprising: an elongated shaft assembly defining a longitudinal tool axis (LT-LT); a surgical end effector comprising: an elongated channel movably coupled to the elongated shaft assembly for selective pivotal travel about a pivot axis (A-A) that is transverse to said longitudinal tool axis upon application of articulation motions thereto, said elongated channel configured to operably support therein a surgical staple cartridge; and an anvil assembly pivotally coupled to said elongated channel for selective pivotal travel relative thereto between open and closed positions about said pivot axis upon application of closing and opening motions thereto; the surgical instrument further comprising an actuation system operably interfacing with said anvil assembly and said elongate channel to selectively apply said closing and opening motions to said anvil assembly and said articulation motions to said elongated channel; characterized in that said actuation system comprises: an actuation pivot movably supported by said elongated channel and interfacing with said anvil assembly; a proximal cam surface on said actuation pivot operably interfacing with a proximal pin on said anvil assembly; a distal cam surface on said actuation pivot interfacing with a distal pin on said anvil assembly; and a reciprocatable actuation bar operably coupled to said actuation pivot such that movement of said reciprocatable actuation bar to a closure position causes the actuation pivot to apply a closing motion to said anvil assembly and movement of said reciprocatable actuation bar to an articulation position causes said actuation pivot to apply an articulation motion to said elongated channel to cause said elongated channel to pivot about said pivot axis relative to said elongated shaft assembly. an elongated shaft assembly defining a longitudinal tool axis (LT-LT); a surgical end effector comprising: an elongated channel movably coupled to the elongated shaft assembly for selective pivotal travel about a pivot axis (A-A) that is transverse to said longitudinal tool axis upon application of articulation motions thereto, said elongated channel configured to operably support therein a surgical staple cartridge; and an anvil assembly pivotally coupled to said elongated channel for selective pivotal travel relative thereto between open and closed positions about said pivot axis upon application of closing and opening motions thereto; an elongated channel movably coupled to the elongated shaft assembly for selective pivotal travel about a pivot axis (A-A) that is transverse to said longitudinal tool axis upon application of articulation motions thereto, said elongated channel configured to operably support therein a surgical staple cartridge; and an anvil assembly pivotally coupled to said elongated channel for selective pivotal travel relative thereto between open and closed positions about said pivot axis upon application of closing and opening motions thereto; the surgical instrument further comprising an actuation system operably interfacing with said anvil assembly and said elongate channel to selectively apply said closing and opening motions to said anvil assembly and said articulation motions to said elongated channel; characterized in that said actuation system comprises: an actuation pivot movably supported by said elongated channel and interfacing with said anvil assembly; a proximal cam surface on said actuation pivot operably interfacing with a proximal pin on said anvil assembly; a distal cam surface on said actuation pivot interfacing with a distal pin on said anvil assembly; and a reciprocatable actuation bar operably coupled to said actuation pivot such that movement of said reciprocatable actuation bar to a closure position causes the actuation pivot to apply a closing motion to said anvil assembly and movement of said reciprocatable actuation bar to an articulation position causes said actuation pivot to apply an articulation motion to said elongated channel to cause said elongated channel to pivot about said pivot axis relative to said elongated shaft assembly. an actuation pivot movably supported by said elongated channel and interfacing with said anvil assembly; a proximal cam surface on said actuation pivot operably interfacing with a proximal pin on said anvil assembly; a distal cam surface on said actuation pivot interfacing with a distal pin on said anvil assembly; and a reciprocatable actuation bar operably coupled to said actuation pivot such that movement of said reciprocatable actuation bar to a closure position causes the actuation pivot to apply a closing motion to said anvil assembly and movement of said reciprocatable actuation bar to an articulation position causes said actuation pivot to apply an articulation motion to said elongated channel to cause said elongated channel to pivot about said pivot axis relative to said elongated shaft assembly.