The OECD-LOFT Project, in which 12 organizations from 10 OECD countries participated, was an international reactor safety program organized through NEA of OECD. It used the LOFT (Loss-of Fluid Test) nuclear test facility at the Idaho Engineering National Laboratory (INEL). Switzerland actively participated the OECD-LOFT program. Swiss contributions can be summarized as: - performing post-test analyses using various computer programs, - joining the project by sending a delegate (the author) between 1983 to 1985 to Idaho Falls USA where the project was conducted. He took part in the activities associated directly with the experiment planning and post-experiment analysis. Another delegate was also sent to Idaho Falls during the post-test phase of the last experiment, -contributing the project review at the Program Review Group and Management Board levels, - chairing the Program Review Group of the LOFT-OECD project for about three years, - performing analysis using the samples obtained from the first fission product experiment in the hot laboratory of PSI. This `Abschluss` report is intended to provide an overview not only on the activities for the Extended OECD-LOFT Program but also on the previous OECD-LOFT Program for which the Swiss contribution was also financed by BEW. (author) 26 refs.