An articulation joint for a surgical instrument that includes an elongate shaft assembly and a drive system that is configured to generate and apply a plurality of rotary control motions to the elongate shaft assembly, the articulation joint comprising: a proximal joint portion coupled to the elongate shaft assembly; a distal joint portion movably coupled to the proximal joint portion and configured to interface with a surgical end effector, wherein the distal joint portion is configured to pivot relative to the proximal joint portion about a transverse axis; a first gear train operably interfacing with a proximal firing shaft portion of the elongate shaft assembly and a distal firing shaft portion operably interfacing with the surgical end effector for transmitting a rotary firing motion from the proximal firing shaft portion to the surgical end effector while facilitating articulation of the distal joint portion relative to the proximal joint portion, wherein the first gear train comprises a distal drive shaft gear coupleable to the distal firing shaft portion, a proximal drive shaft gear coupled to said proximal firing shaft portion and a drive shaft transfer gear, situated between said proximal drive shaft gear and said distal drive shaft gear and rotatable about the transverse axis; and a second gear train operably interfacing with a proximal shaft portion of the elongate shaft assembly for transmitting a distal control motion to the surgical end effector, wherein the second gear train comprises an output gear, an input gear coupleable to said proximal rotation shaft portion and a transfer gear, located between said output gear and said input gear, and rotatable about the transverse axis; wherein the distal control motion is a distal rotational control motion and the second gear train transmits the distal rotational control motion to cause the surgical end effector to rotate relative to the elongate shaft assembly while facilitating articulation of the distal joint portion relative to the proximal joint portion, said articulation joint being characterized in that the first gear train is nested within the second gear train. a proximal joint portion coupled to the elongate shaft assembly; a distal joint portion movably coupled to the proximal joint portion and configured to interface with a surgical end effector, wherein the distal joint portion is configured to pivot relative to the proximal joint portion about a transverse axis; a first gear train operably interfacing with a proximal firing shaft portion of the elongate shaft assembly and a distal firing shaft portion operably interfacing with the surgical end effector for transmitting a rotary firing motion from the proximal firing shaft portion to the surgical end effector while facilitating articulation of the distal joint portion relative to the proximal joint portion, wherein the first gear train comprises a distal drive shaft gear coupleable to the distal firing shaft portion, a proximal drive shaft gear coupled to said proximal firing shaft portion and a drive shaft transfer gear, situated between said proximal drive shaft gear and said distal drive shaft gear and rotatable about the transverse axis; and a second gear train operably interfacing with a proximal shaft portion of the elongate shaft assembly for transmitting a distal control motion to the surgical end effector, wherein the second gear train comprises an output gear, an input gear coupleable to said proximal rotation shaft portion and a transfer gear, located between said output gear and said input gear, and rotatable about the transverse axis; wherein the distal control motion is a distal rotational control motion and the second gear train transmits the distal rotational control motion to cause the surgical end effector to rotate relative to the elongate shaft assembly while facilitating articulation of the distal joint portion relative to the proximal joint portion, said articulation joint being characterized in that the first gear train is nested within the second gear train.