[en] The third in a series of international Leak-Before-Break (LBB) Seminars supported in part by the US Nuclear Regulatory Commission was held at TEPCO Hall in the Tokyo Electric Power Company's (TEPCO) Electric Power Museum on May 14 and 15, 1987. The seminar updated the international policies and supporting research on LBB. Attendees included representatives from regulatory agencies, electric utility representatives, fabricators of nuclear power plants, research organizations, and university professors. Regulatory policy was the subject of presentations by Mr. G. Arlotto (US NRC, USA), Dr. H. Schultz (GRS, W. Germany), Dr. P. Milella (ENEA-DISP, Italy), Dr. C. Faidy, P. Jamet, and S. Bhandari (EDF/Septen, CEA/CEN, and Framatome, France), and Mr. T. Fukuzawa (MITI, Japan). Dr. F. Nilsson presented revised nondestructive inspection requirements relative to LBB in Sweden. In addition, several papers on the supporting research programs discussed regulatory policy. Questions following the presentations of the papers focused on the impact of various LBB policies or the impact of research findings. Supporting research programs were reviewed on the first and second day by several participants from the US, Japan, Germany, Canada, Italy, Sweden, England, and France