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Abstract This paper presents a case study of survey and anti-collision risk management for an extended reach well with Total Depth slightly over 29,000 ft. With narrow geological targets and ∼50 ft center-to-center distance to an offset well that had to be maintained throughout the lateral, even the most advanced surveying tools could not provide the required accuracy. Execution was only possible through a new technique of fusion of magnetic and gyro surveys. Combined with passive magnetic ranging while drilling the lateral to achieve the well objectives. During drilling of the intermediate sections, a survey correction workflow was applied using an automated platform. This platform processed surveys acquired with gyro-while drilling (GWD) and magnetic measurement-while-drilling (MWD) tools, along with data from an at-bit inclination sensor. Surveys were combined through weighted averaging for each drilled stand to statistically reduce errors. Before fusion, inclination data were corrected for misalignment SAG, and MWD azimuths were corrected using in-field referencing (IFR) and the multi-station algorithm (MSA). Final MEMS drop gyro surveys were fused with processed drilling surveys. High frequency Definitive Dynamic Surveys (DDS) enabled passive magnetic ranging (PMR) to maintain safe offset distance after landing. At 25,130 ft MD, survey processing resulted in a positional uncertainty of 43 ft in the high-side direction and 96 ft laterally (2D, 95% confidence level). This level of accuracy enabled the well trajectory, located at 56°N latitude, to meet the geological target and anti-collision requirements, representing an approximate 20% improvement over the most accurate individual tool performance. PMR provided additional safety while drilling in close proximity to the offset well. The innovative solution improved accuracy beyond the current limits of the most advanced individual tools by fusing four independent wellbore survey measurements. Given the complexity of the corrections and the volume of data involved, the use of an automated survey processing platform was critical. The platform made individual solutions, including SAG, MSA, and IFR straightforward and enabled the real-time fusion workflow. It provided directional drillers with actionable outputs in real time for effective steering decisions while drilling. The full 6-axis MWD dynamic surveys without requiring stationarity were used for PMR, utilizing residual magnetic interference to determine direction and distance to the offset casing. Yard measurements on similar casing defined detection thresholds and input parameters for accurate modeling. The innovative fusion of survey measurements from three independent tools while drilling, combined with a fourth tool post-drilling surveys, enabled the wellbore positioning accuracy to penetrate a 148 × 148 ft lateral and 60 × 60 ft TVD target. An automated survey correction platform ensured fast processing of complex data in real time, reducing uncertainty. Additionally, the real-time PMR enabled safe drilling close to the offset well.