A series of nine interviews was conducted with recognized experts in the field of institutional internal security in order to gain insight into the insider threat to nuclear facilities. The results of these interviews included the defining of fundamental problems in internal security, the identification of typical bases of conspiracy formation, and the naming of possible options for improving the quality of nuclear safeguards, both through personnel policies and internal controls. Tables and footnotes are included. Appended materials present a rebuttal to a report on material control and memos about visits to various facilities. (Author abstract modified)