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AbstractHydraulic proppant fracturing is developing rapidly in the oil fields in western Siberia and is seen as the most important means to improve oil production from both existing and newly drilled wells. The oil fields vary in size and reservoir quality, with a majority of the developed fields showing permeabilities of 1 to 30 mD. Reservoirs are layered, and fracturing vertical wells in general seems to give higher productivity compared to horizontal wells that are not being hydraulically fractured. This result is most likely because the vertical permeability is much lower than the horizontal permeability.To maximize production from these wells, coarse-sized proppant must be placed using the least-damaging and lowestviscosity fluid systems. For production optimization, the trend is currently "larger (proppant sizes) and bigger (jobs)," using the lowest acceptable polymer loading in the frac fluids, which minimizes gel damage.This paper describes the conflicts that can arise between the requirement to place large amounts of coarse propping material using low viscosity fluids and the perforation size and condition that is needed to do so. These conflicts can lead to job scenarios in which screenouts take place.During fracturing operations in wells in west Siberia, some screenouts did take place. An investigation of the screenouts revealed that the major cause of the screenouts is reduced width development at the perforations associated with the "stress cage." Guidelines were developed to reduce the influence of the near-wellbore stress cage and prevent screenouts. In addition to these guidelines, future solutions are proposed that may avoid the stress cage and place coarse proppant more efficiently.