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Abstract High-angle deviated wells drilled in heterogeneous carbonate reservoirs are frequently challenged by a combination of severe lost circulation, wellbore instability, excessive torque and drag, and recurrent stuck pipe events, all of which can significantly compromise drilling efficiency and well delivery. This paper details the successful planning and execution of a high-risk deviated well in one of challenging Middle East fields, where these issues had historically governed drilling performance. Through the application of an integrated engineering and execution strategy, the study wells were drilled and completed approximately 35% faster than previous wells of comparable profile and complexity, achieving an average drilling performance of approximately 610 ft/day from spud to total depth (TD). This paper presents a detailed field-scale case study where a section-specific and integrated engineering approach enabled a step-change improvement in drilling performance across high-risk deviated wells. The study focuses on two critical hole sections that historically governed overall well delivery performance: the 12¼-in intermediate and deviated section and the 8½-in production and deviated section. These sections exhibited distinctly different dominant failure mechanisms, necessitating tailored mitigation strategies aligned with their specific drilling risks. In the 12¼-in intermediate section, drilling performance is primarily constrained by severe to total losses encountered across fractured carbonate intervals, in addition to elevated surface torque and suppressed rate of penetration (ROP). Historically, losses were mitigated through the placement of multiple loss-circulation cement plugs (LCPs). While this approach occasionally restored circulation, it frequently resulted in significant non-productive time due to recurrent losses after drilling out the cement, prolonged remedial operations, increased risk of stuck pipe during placement and plug drill-out, and, in several cases, sidetracks initiated while attempting to regain wellbore integrity. In contrast, the 8½-in section is dominated by wellbore instability manifested as tight hole conditions and recurrent stuck bottomhole assembly (BHA) incidents due to shale instability. Post-well analysis demonstrated that these events were strongly correlated with wellbore trajectory orientation (inclination and azimuth) relative to the mud-weight requirement. To address these section-specific challenges, tailored mitigation strategies were implemented for each section. In the 12¼-in section, drilling performance was first improved through the introduction of a revised motorized RSS (rotary steerable system) BHA, which enhanced torque management and drilling efficiency, enabling stable drilling from shoe to shoe while achieving the planned landing inclination and dogleg severity. This change resulted in a reduction in surface torque of up to 30% and an improvement in rate of penetration of approximately 40%, translating into a time saving of 1 day per well for this section. In parallel, the historical reliance on loss-circulation cement plugs (LCPs) was eliminated after introducing several loss-prevention and mitigation control measures using conventional lost-circulation materials (LCM), significantly reducing non-productive time associated with remedial cementing operations. In the 8½-in production section, a geomechanics-driven trajectory optimization combined with a split-BHA configuration and enhanced drilling fluid formulation enabled stable drilling and tripping operations without encountering instability-related events. The integrated execution eliminated stuck pipe incidents and sidetracks previously observed in offset wells and contributed to a reduction of non-productive time from up to approximately 15 days on average in offset wells to 0-1.4 days in the study wells. The effectiveness of the implemented approach was subsequently validated through replication in multiple follow-on deviated wells, confirming that the solutions are reliable and applicable across similar wells.