Parallel to the US Department of Energy (US DOE) Nuclear Power 2010 (NP2010) programme (see Chapter 2, Section 2.2), which focused on advanced light water reactors (ALWRs), in early 2001 the US DOE’s Office of Nuclear Energy, under the leadership of William Magwood IV, assembled the Generation IV (Gen IV) Roadmap Committee to (a) assess competing advanced nuclear energy systems, and (b) determine a common international framework within which member nations could share the research, development and demonstration (prototyping) of Gen IV technologies, while potentially competing in commercial markets by 2030. Member countries and organisations of the Gen IV International Forum (GIF) have included Argentina, Brazil, Canada, China, Euratom, France, Japan, Korea, Russia, South Africa, Switzerland, the United Kingdom and the United States. The early Gen IV Roadmap Committee was composed of policy committees, a cross-cutting Evaluation Methodology Group (EMG) and a number of technical working groups, each focused on a different reactor technology (water, gas, metal and other). These include the gas-cooled fast reactor (GFR), the lead-cooled fast reactor (LFR), the molten salt reactor (MSR), the super-critical water reactor (SCWR), the sodium-cooled fast reactor (SFR) and the very high temperature gas reactor (VHTR). These are extensions of the different reactor types illustrated in Chapter 1, Figure 1.2.