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Abstract Reliability-based material selection (RBMS) can directly quantify the probability of failure associated with a specific tubing and/or production liner design based upon the material selection. By comparing carbon steel versus corrosion-resistant alloys (CRAs) or various CRAs, this approach can help evaluate the tubular design and find the optimal risk-cost balance decision for existing and large new gas field developments located both onshore and offshore; notably for those with non-negligible hydrogen sulfide (H2S) and carbon dioxide (CO2) content. The RBMS procedure starts by developing time-dependent load variables that include the wellbore geometries, reservoir model predictions of bottom-hole pressure, bottom-hole temperature, H2S, CO2, water content and anticipated load data and calculating time-dependent strength variables that encompass historical material and dimensional data, tubing hydraulics, corrosion and cracking testing of carbon steel and CRAs materials with actual produced fluid from the exploration wells in the gas field. Then the RBMS process uses limit-state functions that yield a time-dependent probability of failure for the tubing string. Finally, based on project economics and gas penalties, time-dependent risk-weighted costs are estimated for the selected materials (carbon steel versus CRA or CRA versus CRAs) for the tubing string or production liner. RBMS has been applied for a large gas field development of 10 wells over a period of 25 years with 10,000-foot tubing strings and 3,000-foot production liner strings. Probabilistic models have helped calculate the reliability of each of the materials selected, L80 and CRA-28 grades, for the loads and conditions of the production tubing strings during the predicted life of each gas field. As a result, determining the risk-weighted net present value (NPV) for all the materials selected as a function of time yielded an optimized design as a function of cost and reliability. The application of RBMS showed that the project economics for large gas developments can be substantially impacted with cost savings for an operator in the order of tens of millions of dollars. By using RBMS, engineers and managers can evaluate the design of tubulars and come to the optimal risk-cost balanced decision point based on project economics. Thus, operators can release the total potential of existing and new large gas field developments.