A surgical system, comprising: a surgical instrument, comprising: a shaft assembly defining a longitudinal axis; an end effector disposed adjacent a distal portion of the shaft assembly; a control rod extending at least partially through the shaft assembly and being disposed in mechanical cooperation with the end effector, wherein rotation of the control rod effects a function of the end effector; and the surgical instrument further comprising a control assembly disposed in mechanical cooperation with the end effector, the control assembly comprising a first articulation control including a first manually rotatable element, wherein rotation of the first manually rotatable element induces a differential tension and a corresponding motion in two steering cables (313,315) causing the end effector to move from a first position where the end effector is substantially parallel to the longitudinal axis to a second position where the end effector is disposed at an angle with respect to the longitudinal axis; and a first handle assembly configured for selective mechanical engagement with the control rod of the surgical instrument, the first handle assembly including a power source and a drive member, the power source being actuatable to rotate the drive member about the longitudinal axis; wherein the control assembly includes a second articulation control including a second manually rotatable element, wherein rotation of the second manually rotatable element induces a differential tension and a corresponding motion in two other steering cables (323,325) causing the end effector to move from the first position where the end effector is substantially parallel to the longitudinal axis to a third position where the end effector is disposed at an angle with respect to the longitudinal axis and at an angle with respect to the second position, and wherein the second manually rotatable element is individually operable from the first manually rotatable element of the first articulation control. a surgical instrument, comprising: a shaft assembly defining a longitudinal axis; an end effector disposed adjacent a distal portion of the shaft assembly; a control rod extending at least partially through the shaft assembly and being disposed in mechanical cooperation with the end effector, wherein rotation of the control rod effects a function of the end effector; and the surgical instrument further comprising a control assembly disposed in mechanical cooperation with the end effector, the control assembly comprising a first articulation control including a first manually rotatable element, wherein rotation of the first manually rotatable element induces a differential tension and a corresponding motion in two steering cables (313,315) causing the end effector to move from a first position where the end effector is substantially parallel to the longitudinal axis to a second position where the end effector is disposed at an angle with respect to the longitudinal axis; and a shaft assembly defining a longitudinal axis; an end effector disposed adjacent a distal portion of the shaft assembly; a control rod extending at least partially through the shaft assembly and being disposed in mechanical cooperation with the end effector, wherein rotation of the control rod effects a function of the end effector; and the surgical instrument further comprising a control assembly disposed in mechanical cooperation with the end effector, the control assembly comprising a first articulation control including a first manually rotatable element, wherein rotation of the first manually rotatable element induces a differential tension and a corresponding motion in two steering cables (313,315) causing the end effector to move from a first position where the end effector is substantially parallel to the longitudinal axis to a second position where the end effector is disposed at an angle with respect to the longitudinal axis; and a first handle assembly configured for selective mechanical engagement with the control rod of the surgical instrument, the first handle assembly including a power source and a drive member, the power source being actuatable to rotate the drive member about the longitudinal axis;