Flexicoking is a residuum conversion process which integrates coke gasification, with conventional fluid coking. Coke Gasification is one of the oldest commercial chemical operations; fluid coking is an established refinery process with a total installed capacity of about 150 MB/SD. Flexicoking provides a refiner with increased flexibility and the capability of producing high yields of clean, light petroleum products from relatively poor quality crudes, while complying with strict air and water pollution regulations. A Flexicoker can convert about 98% of a typical vacuum residuum into liquid and gaseous products. About 95% of the total sulfur in the residuum can be recovered from the fuel product by commercially available processes. Most of the combined nitrogen in the resid is converted either to elemental nitrogen or to other forms which can readily be controlled to acceptable levels by conventional treating processes. About of the metals in the feed are concentrated in a small solids purge from the system.The paper reviews pertinent background information in support of this advanced coking process. The results of some of the engineering and laboratory studies, which were part of the development of Flexicoking, are summarized. And finally, examples of how this process can be used in specific refinery situations are presented.