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Abstract Increased plugging and abandonment (P&A) activities demand efficient and cost-effective solutions to safely install cross-sectional cement barriers. This paper presents a review of perf, wash, and cement (PWC) operations performed in Malaysia using the jet-based type PWC tool. Over the past ten years, that has amounted to a track record of 42 cross-sectional cement barriers installed in different casing sizes, configurations, and well inclinations. Installing qualified cross-sectional cement barriers is a difficult task. Traditional methods such as section milling and cement squeeze have been ineffective in delivering good results in terms of time, cost, and quality, which prompted the development of new placement techniques. PWC, born in this context, is a mature technology with an established track record, qualified according to global standards, and capable of improving on these issues. The cement barrier is installed in a sequence of perforating the desired interval (gun-based or mechanical), pumping a wash fluid to clean the annulus, then a spacer fluid, and finally cement. As with many wells worldwide, wells in Malaysia also suffer from severe well integrity issues, such as poor cement sheaths and sustained annulus pressure. PWC fixes these by establishing a cross-sectional cement barrier that provides zonal isolation while still enabling access to the well below the installation depth, should it be required for re-completion purposes. A review of all jobs shows that the 41 barriers have been installed in 33 wells, as some wells may require multiple barriers to restore isolation before abandonment. 33 barriers were installed in single casing configurations (either in an open hole annulus or in an interval in front of another outermost casing), while 8 were done in dual casing configurations (i.e., washing and cementing happen in two annuli at the same time). Jobs were also performed at different casing sizes (7", 7-5/8", 9-5/8", 10-3/4", and 13-3/8") with open holes ranging from 8.5" up to 17.5". Well inclinations ranged from nearly vertical wellbores up to 65 degrees. Furthermore, some of the jobs were carried out with mechanical perforations, which can simplify logistics by avoiding explosives. Lessons learned were collected along the way, further improving procedures. This review highlights the advantages of PWC over traditional methods for annular remediation during plugging and abandonment activities and general zonal isolation to fix well integrity issues. Focus is given to the track record established in Malaysia over the past ten years, encompassing 42 plugs that have been installed. Lessons learned are discussed and provide insights that can strengthen procedures in Malaysia and also be helpful to jobs performed around the world.