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Abstract High-frequency torsional oscillations (HFTO) are excited by the PDC-bit rock interaction and lead to damaging vibrational loads. In at least 20 % of the drilling time HFTO is the most pronounced performance limiter: to keep the loads within the specifications of the bottom-hole assembly (BHA), the drilling parameters need to be limited which reduces the rate of penetration. A rotary steerable system with HFTO mitigation capability was developed to remove this obstacle and fully mitigate HFTO. This paper discusses the technology considering HFTO mitigation capabilities, influence on reliability measures, drilling efficiency, and BHA properties in a holistic analysis. The performance of a near bit HFTO damper is analyzed for different BHAs, bits, environments and in critical drilling scenarios. In a study with >150 runs with the damper HFTO mitigation performance, reliability performance indicators, and rate of penetration are compared with runs without the damper. Further, the HFTO mitigation capabilities with superimposed stick/slip based on field data. The findings are summarized in maps that highlight the damper performance for combinations of weight-on bit and bit rotary speed, discussing tool limits, drilling performance, and reliability performance indicators. The case study shows that HFTO is mitigated in more than 99 % of the circulating time. The tool performs well removing damaging HFTO frequencies between 170 Hz and 320 Hz related to different BHAs with and w/o mud motors by 100 %. Thus, ROP can be increased by higher WOB and higher bit rotary speed but needs to be managed based on mud motor and drill bit limitations. The data shows that the performance is not impacted by superimposed stick/slip that is strongly coupled with HFTO resulting in increased damping requirements. Reliability measures are enhanced significantly compared to benchmark runs by removing all HFTO-related failures and reducing the non-productive time and related costs significantly. HFTO as the major performance limiter during drilling is removed by the RSS system with HFTO mitigation capability. Previously, optimizing bits required balancing increased ROP against the risk of generating high-frequency torsional oscillations. Effective damping significantly reduces this constraint, enabling bits to achieve higher ROP without triggering excessive HFTO. As shown in the runs, the full potential can be raised with a holistic approach that considers all components of the BHA. This enables a significant increase of reliability and drilling efficiency for a HFTO prone applications and environments.