At the SPE conference in 2006 BP announced the Field of the Future Integrated Surveillance Information System (ISIS) project. Since then the ISIS system has been developed, delivered, tested and verified. Deployment to BP assets has been at the scale and pace proposed in the conference papers published at that time. This paper describes a core module, the Rate&Phase virtual flow meter, and also gives reasons why deployment has been achieved so successfully.BP's Rate&Phase system automatically estimates production rates from individual wells and other well performance and reservoir information at least once per hour. The approach has been to automate a proven Petroleum Engineering methodology using models of well hydraulics and flow though chokes. The system takes advantage of the instrumentation typically installed on new wells and the transmission of those data for analysis at technical centres often remote from the production sites. Rate&Phase is integrated in ISIS along with routines to automatically reconcile production across entire fields, monitor issues of erosion and sand production and estimate reservoir pressure at shut-ins.The Rate&Phase system has been deployed widely across BP-operated assets including many major oil and gas fields. Benefits have been realised from the ability to efficiently monitor well stock, manage fields better and allocate production more accurately. The effort to determine monthly production allocation is significantly reduced. Production gains have been realised through assets operating closer to constraints because of the assurance of flow rates in critical pipework. Developments are being introduced to reduce maintenance effort through tools to assist model re-calibration and to complement the hydraulic models with models derived entirely from measured data.Rate&Phase exploits commonly-used modelling tools and is designed to be easy to deploy/configure. Acceptance of the system has been hastened because it is not regarded as a black box and all results can be reproduced manually offline. Current production and performance information is readily available and changes over time can be trended though existing data interfaces.