The Journal of Nuclear Energy Science & Power Generation Technology publishes the Latest Research in Reactor Design. It covers all the major fields and interdisciplinary aspects of Reactor Design but does not limit to it. It also covers Nuclear Energy Research, Nuclear Engineering, Nuclear Materials & Fuel Research, Applied Nuclear Chemistry, Reactor Engineering & Design, Nuclear Thermal Hydraulics, Nuclear Instruments and Methods, Nuclear Waste Management, Radiological Safety Analysis, Reactor Construction, Nuclear Energy Policy, Radiation Measurement and Exposure Control, Fusion and Plasma Energy Research. The nuclear power industry has been developing and improving reactor technology for more than five decades with innovative engineering designs. Two major international initiatives have been launched to define future reactor and fuel cycle technology, mostly looking further ahead than the main subjects of this paper: Generation IV International Forum (GIF) is a US-led grouping set up in 2001 which has identified six reactor concepts for further investigation with a view to commercial deployment by 2030. See Generation IV paper and DOE web site on "4th generation reactors".