"This Technical Working Group was charged with the identification and evaluation of advanced water-cooled reactor concepts. The initial activity was the assessment and 'screening for potential' of candidate systems. Advanced water-cooled reactor concepts were identified via a formal DOE 'Request for Information' (RFI) issued in April 2001. This process resulted in submittal of 30 advanced water reactor concepts by researchers and industry experts in Argentina, Brazil, Canada, France, Italy, Japan, Korea, and the U.S. In addition, the technical working group itself developed information on eight concepts, yielding a total of 38 concepts for evaluation. The technical working group consolidated all but one of the 38 reactor and fuel cycle concepts into nine distinct concept sets, based on their key common features. The technical working group then conducted a preliminary evaluation of these nine sets in order to determine their potential to achieve the Generation IV goals."