Underwater welders combine commercial diving with advanced welding skills to work on submerged structures such as ship hulls, offshore rigs, pipelines, and underwater infrastructure. They conduct wet welding in open water and dry hyperbaric welding in pressurized chambers. The role demands exceptional physical fitness, precision, and ability to work under hazardous environmental conditions. Global demand is driven by offshore energy, marine transport, and underwater infrastructure maintenance. Training is rigorous and safety-intensive, with high earning potential but elevated risk. Increasing offshore development and aging marine assets sustain continued demand for specialized underwater welders.