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Abstract Thanks to the advancements in and convergent of the two technologies of horizontal well drilling and hydraulic fracturing, the oil production from tight formations has become possible and economic. While hydraulically fractured horizontals wells (HFHW) have increased the productivity of these reservoirs, these wells typically see a sharp decline in hydrocarbon rate due to tight nature of these reservoirs. Operators have improved oil recovery methods in these formations with the successful application of the secondary recovery method of waterflooding. This combination of HFHW and waterflooding has primarily been implemented in Canadian tight oil formations such as the Canadian Bakken Shale, lower Shaunavon, Viking, Belly River and Cardium. With the application of waterflooding on these HFHW, the one issue that operators are facing is the management of quick water breakthrough due to well to well communication through the network of induced or natural fractures resulting in poor sweep efficiency of waterfloods. Conformance improvement using polymer gel technology, a polymer and a polymer specific cross-linker, has been a common practice in conventional assets for 30 years. The polymer solution is mixed with the crosslinker on the surface and the mixture becomes more viscous (due to the reaction between polymer and crosslinker) as it is pumped downhole and into the reservoir. The application of polymer gel technology in unconventional tight oil water floods requires a new approach and is most successful when approached in a systematic way starting with proper diagnosis and candidate selection followed by engineering design and field execution. After candidate selection and diagnosis of communication between wells, a treatment design is put together based on the level of communication as measured by the transit time between the two wells. The conformance treatment is implemented by bull heading the mixture of polymer and crosslinker and sequentially increasing the gel strength by increasing polymer concentration at fixed polymer to crosslinker ratio. The idea is to build pressure continuously throughout the treatment, an indication of polymer gel filling up the path of communication. A new application for gel conformance technology, in tight oil waterfloods, as a cost-effective solution, to address the well to well communication and improve sweep efficiency is discussed in this article. Relatively smaller size and lower strength of gel, compared to the typical applications, makes the application of polymer gel in HFHWs unique and very effective. This paper will review multiple campaigns in Canadian Bakken from 2016 to 2018 and discuss the rate of success, incremental oil produced and longevity of these treatment. Opportunities to further optimize these treatments and the pitfalls have been recognized and discussed.