Abstract: Method and apparatus for three-phase fluid flow measurement that operates reliably and accurately over a wide range of gas cut. The system uses a fluid conditioner to separate the three-phase fluid flow into a liquid rich component and a gas rich component. The gas flow rate of the gas rich component is controlled by a valve to maintain the gas cut at a predetermined level. The valve is responsive to control signals generated by a measurement apparatus that measures oil, gas, and water cuts. The system configuration includes a pipeline for carrying the liquid rich component, a gas line for carrying the gas rich component, and a measurement line in parallel with the pipeline.