[en] Instruments developed for safeguards and the domestic nuclear industry to nondestructively assay nuclear materials are being used in unattended and remote monitoring applications. In large facilities, such instruments can be combined with more classical surveillance methods. The effective implementation of such systems involves the integration of physics knowledge and measurement experience, detectors and their supporting electronics, and computers and their software. Los Alamos has been involved in three types of applications: (a) radiation triggers for video surveillance, (b) unattended assay of materials moving in automated fabrication and process plants, and (c) monitoring radiation signatures to verify the movement of irradiated and unirradiated nuclear material