The Institut francais du petrole has developed a new natural gas treatment technique, the integrated IFPEXOL process, based on the use of methanol at low temperature, acid which includes 3 functions in only one step: dehydration, NGL recovery and acid gases removal. The IFPEXOL process is split into two successive sections: IFPEX-1 removes NGL and water, IFPEX-2 removes the acid gases when necessary. For each section, the influence of the main parameters on the process performances is examined. After a research and development program at laboratory scale and on a pilot plant, the IFPEXOL process has reached the industrial step. The first IFPEX-1 unit has started up in June 1992 in Canada at Petro-Canada＇s East Gilby field. Subsequently, 11 other units, of which 7 are running, have been licenced. The results obtained from the industrial plants confirm the simulation models. The IFPEX-2 section is in its marketing phase.