Safe operation with cost effective is critical in the oil and gas industry especially for offshore projects. This invited session contains excellent papers that cover all the key components from understanding subsurface/ geological complexities, appropriate surveillance method, qualitative interpretation, and prediction by using machine learning and cutting-edge technology to ensure risk reduction and operational success. This section will be a great learning opportunity to broad audience of reservoir engineers, geoscientists, drillers, technological experts, service companies, as well as consultants to experience achievements and what are the remaining challenges and how all disciplines can work together in the era of digital transformation for a safe, successful project with an effective cost.