Surge is a dramatic collapse of flow within a centrifugal compressor which results in reverse flows and potential damage to bearings and other compressor components. The traditional approach to avoiding surge is to recycle flow to maintain a selected minimum rate. However, current external surge control systems result in opening the recycle valve sooner and maintaining a higher flow rate than necessary, which reduces the efficient operating range, wastes fuel, and significantly increases the cost of compressor operation. If an improved surge control system that senses the approach of surge can be implemented, then compressors can be controlled close to surge while avoiding damage. Such a Direct Surge Control System will increase operating range and flexibility and reduce the operating costs of avoiding surge. The Direct Surge Control System described in this paper results from a multi-year research project that is funded by the Department of Energy's (DOE) Office of Fossil Energy and managed by the National Energy Technology Laboratory (NETL) as part of their Natural Gas Infrastructure Reliability Program. The project is co-funded by GMRC and Siemens Energy and Automation, who is participating in the overall project s the surge controller developer and the commercialization partner. This paper presents a brief background, some laboratory test results, and a complete description of the Direct Surge Control System that is being developed and prototype tested at this time. This paper explains the step-by-step process for implementing Direct Surge Control in modern centrifugal compressors. In order to retrofit a field compressor with the current state of this technology, the impeller needs to be of a modern 3D geometry, a drag probe has to be designed (Sized) and fabricated for the gas velocity and density range, a drag probe has to be installed close to the impeller inlet within the compressor with wiring securely mounted and penetrating the compressor's pressure boundary, and the signal needs to be connected to a surge controller designed to use the resulting internal flow recirculation signals. Implementing this improved surge control, that results from this GMRC/DOE research, is not trivial but it has the potential to be cost effective and worthwhile.