A robotic surgical system configured to control movement of a first instrument and a second instrument, each of which is on a robotic manipulator. In described modes of operation, movement of the first instrument is surgeon controlled based on surgeon input to the robotic system. Movement of the second instrument is also surgeon controlled, but its motion is defined by the chosen mode of operation which sets the amplitude and direction of the second instrument's motion relative to the actual or instructed motion of the first instrument. In this way, two instruments are simultaneously moved based on input from a single surgeon input device.