While the public is generally aware of the use of hydraulic fracturing for unconventional resource development onshore, it is less familiar with the well completion and stimulation technologies used in offshore operations, including hydraulic fracturing, gravel packs, "fracpacks, " and acid stimulation. Just as onshore technologies have improved, these well completion and stimulation technologies for offshore hydrocarbon resource development have progressed over many decades. To increase public understanding of these technologies, the National Academies of Sciences, Engineering, and Medicine established a planning committee to organize and convene a workshop on Offshore Well Completion and Stimulation: Using Hydraulic Fracturing and Other Technologies on October 2-3, 2017, in Washington, DC. This workshop examined the unique features about operating in the U.S. offshore environment, including well completion and stimulation technologies, environmental considerations and concerns, and health and safety management. Participants from across government, industry, academia, and nonprofit sectors shared their perspectives on operational and regulatory approaches to mitigating risks to the environment and to humans in the development of offshore resources. This publication summarizes the presentations and discussions from the workshop.