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Abstract This paper presents the results of research programs performed by OAO TATNEFT aimed at additions to reserves and increased production from non-conventional reservoirs found in Tatarstan. It is worth mentioning that TATNEFT has been studying non-conventional reservoirs since 1950s. To date, most of Tatarstan's oil fields have entered their closing stage of development with 86% cumulative production of OOIP and increase of hard-to-recover reserves share from 33% to 80%. A considerable part (36%) of TATNEFT hard-to-recover reserves falls on carbonate low-permeability sediments with low-thickness fractured reservoirs. Aiming at study of shale, or tight, oil in the territory of Tatarstan, TATNEFT has concentrated its efforts on the search for oil accumulations and study of low-permeability reservoirs and source rocks in the Tournaisian-Sargaevian formations. Prospecting of nonconventional hydrocarbon reserves and nonconventional reservoir study is a challenging, still, a very promising line of activity associated that can add value and yield good returns, considering that the Tournaisian-Sargaevian formations are widespread in Tatarstan, the domanikites are source rocks with high organic matter content, and proved oil potential of these deposits. A certain tight oil potential is also associated with the Samara, Ulyanovsk, Orenburg, Nenets Autonomous District, and Kalmykia leases. It is worth mentioning that evaluation of shale plays is not based on conventional methods involving seismic survey, logging etc., but rather on analysis of chemical-mineralogical and mechanical rock properties. Analysis of available well data has been performed; underway are large-scale core recovery projects, including oriented core and quick capture. Considering geologic environment of the domanikites and the domanikoids in the Volga-Ural oil-and-gas province, petrophysical properties of these rocks, fluid composition and properties, G&G information is analyzed to design hydraulic fracturing treatment in wells targeting the domanikites and the domanikoids. Candidates for hydrofrac jobs have been selected. Dedicated drilling and reservoir management technologies are developed.