Military Intelligence and Security Service (Swedish: Militära underrättelse- och säkerhetstjänsten), MUST, is a division of the Swedish Armed Forces Central Command. It is the main foreign intelligence agency in Sweden and as such is responsible for providing intelligence to both the Government of Sweden and the Supreme Commander of the Swedish Armed Forces. It is also the Military Security Service which means that it is managing the security for vital divisions and agencies of the Swedish Armed Forces.
MUST consists of three departments, Underrättelsekontoret UNDK (Intelligence Office), Säkerhetskontoret SÄKK (Security Office) and Kontoret för Särskild Inhämtning KSI (Office for Special Collection).
UNDK's task is to acquire relevant information which can be used as basis when the Central Command and Ministry of Defence makes decisions, and aids deployed Swedish military units.
SÄKK's task is to work with signal protection, investigating persons and information protection.