A centrifugal compressor performance adjustment system, comprising: a compressor chassis defining an inlet passageway, a diffuser passageway coupled to the inlet passageway, and a return passageway extending from the diffuser passageway; at least one inlet vane located in the inlet passageway; at least one diffuser vane located in the diffuser passageway; a plurality of return vanes located in the return passageway; wherein each of the plurality of return vanes is coupled to the compressor chassis by a return vane coupling; characterized in that the system further comprises: an annular return vane actuation member coupled to each of the plurality of return vanes and operable to rotate about a return vane actuation member axis in order to move the plurality of return vanes relative to the compressor chassis; a plurality of actuation channels defined by the annular return vane actuation member and located about the circumference of the annular return vane actuation member; a return vane pin extending from each of the plurality of return vanes, wherein each return vane pin is located in a respective actuation channel on the annual return vane actuation member; a first actuation rod pivotally coupled to a first arm, wherein the first arm is mounted to a distal end of a translation rod; and a second arm comprising an actuation pin mounted to a distal end of the translation rod such that the actuation pin is opposite the first arm on the translation rod; wherein the annular return vane actuation member is coupled to the first actuation rod through the actuation pin; and wherein the first actuator rod is operable to rotate the annular return vane actuation member about a return vane actuation member axis. a compressor chassis defining an inlet passageway, a diffuser passageway coupled to the inlet passageway, and a return passageway extending from the diffuser passageway; at least one inlet vane located in the inlet passageway; at least one diffuser vane located in the diffuser passageway; a plurality of return vanes located in the return passageway; wherein each of the plurality of return vanes is coupled to the compressor chassis by a return vane coupling; characterized in that the system further comprises: an annular return vane actuation member coupled to each of the plurality of return vanes and operable to rotate about a return vane actuation member axis in order to move the plurality of return vanes relative to the compressor chassis; a plurality of actuation channels defined by the annular return vane actuation member and located about the circumference of the annular return vane actuation member; a return vane pin extending from each of the plurality of return vanes, wherein each return vane pin is located in a respective actuation channel on the annual return vane actuation member; a first actuation rod pivotally coupled to a first arm, wherein the first arm is mounted to a distal end of a translation rod; and a second arm comprising an actuation pin mounted to a distal end of the translation rod such that the actuation pin is opposite the first arm on the translation rod; wherein the annular return vane actuation member is coupled to the first actuation rod through the actuation pin; and wherein the first actuator rod is operable to rotate the annular return vane actuation member about a return vane actuation member axis. an annular return vane actuation member coupled to each of the plurality of return vanes and operable to rotate about a return vane actuation member axis in order to move the plurality of return vanes relative to the compressor chassis; a plurality of actuation channels defined by the annular return vane actuation member and located about the circumference of the annular return vane actuation member; a return vane pin extending from each of the plurality of return vanes, wherein each return vane pin is located in a respective actuation channel on the annual return vane actuation member; a first actuation rod pivotally coupled to a first arm, wherein the first arm is mounted to a distal end of a translation rod; and a second arm comprising an actuation pin mounted to a distal end of the translation rod such that the actuation pin is opposite the first arm on the translation rod; wherein the annular return vane actuation member is coupled to the first actuation rod through the actuation pin; and wherein the first actuator rod is operable to rotate the annular return vane actuation member about a return vane actuation member axis.