On the edge, under water documents offhore diving and the pioneer divers on the Norwegian continental shelf. Historians Kristin Øye Gjerde and Helge Ryggvik have sought to provide a nuanced and broad-based historical presentation, which carries the story from the start of oil exploration on the NCS down to the present day. Divers in the North Sea have been key players in developing the Norwegian oil industry. They helped to establish a new and unknown industry, which presented substantial challenges and the need to move boundaries. The authors write about the divers and their work, technological development and research, the diving companies, unionisation and government regulation. They provide an insight into a tough and risky profession, where accidents and tragedies have made their mark. Engelsk utgave av boken Nordsjødykkerne som ble utgitt i 2009, med oppdatert forord vedr. Strasbourg-dommen.