This report sets out the history and records the significant technical findings of a particularly important international collaboration on nuclear reactor safety, the OECD LOFT Project, in which a number of OECD countries, organized through the NEA, collaborated on a program to use of the LOFT (Loss-of Fluid Test) experimental nuclear test facility at the Idaho National Engineering Laboratory (INEL) in a program of safety experiments. The initial proposal was developed from an initiative of the United States Department of Energy, who also provided continuing management support. The objective of an international team with those of the reactor operation and analysis staff at INEL to provide a significant addition both to the international database of large-scale experimental data on reactor safety and to the analysis and understanding of the test results. 51 refs., 15 figs., 11 tabs.