A system comprising: a first compressor and a second compressor; a heat rejection heat exchanger coupled to the first and second compressors (22, 52) to receive refrigerant compressed by the compressors (22, 52); means for receiving refrigerant from the heat rejection heat exchanger and reducing an enthalpy of a first portion of the received refrigerant while increasing an enthalpy of a second portion, said second portion being returned to the second compressor; a first ejector having: a primary inlet coupled to the means (304, 404) to receive a first flow of the reduced enthalpy refrigerant; a secondary inlet; and an outlet coupled to the first compressor to return refrigerant to the first compressor; a first heat absorption heat exchanger coupled to the means (304, 404) to receive a second flow of the reduced enthalpy refrigerant and upstream of the secondary inlet of the first ejector; a second heat absorption heat exchanger between the outlet of the first ejector and the first compressor; characterized by comprising a second ejector having: a primary inlet coupled to the heat rejection heat exchanger to receive the refrigerant second portion from the heat rejection heat exchanger; a secondary inlet coupled to the first compressor to receive refrigerant from the first compressor; and an outlet; and said means further comprising an economizer heat exchanger having: a first leg coupled to the heat rejection heat exchanger to receive the refrigerant first portion from the heat rejection heat exchanger; and a second leg coupled to the second ejector outlet to receive the second portion. a first compressor and a second compressor; a heat rejection heat exchanger coupled to the first and second compressors (22, 52) to receive refrigerant compressed by the compressors (22, 52); means for receiving refrigerant from the heat rejection heat exchanger and reducing an enthalpy of a first portion of the received refrigerant while increasing an enthalpy of a second portion, said second portion being returned to the second compressor; a first ejector having: a primary inlet coupled to the means (304, 404) to receive a first flow of the reduced enthalpy refrigerant; a secondary inlet; and an outlet coupled to the first compressor to return refrigerant to the first compressor; a primary inlet coupled to the means (304, 404) to receive a first flow of the reduced enthalpy refrigerant; a secondary inlet; and an outlet coupled to the first compressor to return refrigerant to the first compressor; a first heat absorption heat exchanger coupled to the means (304, 404) to receive a second flow of the reduced enthalpy refrigerant and upstream of the secondary inlet of the first ejector; a second heat absorption heat exchanger between the outlet of the first ejector and the first compressor; characterized by comprising a second ejector having: a primary inlet coupled to the heat rejection heat exchanger to receive the refrigerant second portion from the heat rejection heat exchanger; a secondary inlet coupled to the first compressor to receive refrigerant from the first compressor; and an outlet; and a primary inlet coupled to the heat rejection heat exchanger to receive the refrigerant second portion from the heat rejection heat exchanger; a secondary inlet coupled to the first compressor to receive refrigerant from the first compressor; and an outlet; and said means further comprising an economizer heat exchanger having: a first leg coupled to the heat rejection heat exchanger to receive the refrigerant first portion from the heat rejection heat exchanger; and a second leg coupled to the second ejector outlet to receive the second portion. a first leg coupled to the heat rejection heat exchanger to receive the refrigerant first portion from the heat rejection heat exchanger; and a second leg coupled to the second ejector outlet to receive the second portion.