In 2008, recognizing a nascent requirement in the maritime security domain, CJOS COE was requested by NATO Allied Command Transformation (ACT) to provide an overall picture of Maritime Unmanned Systems (MUS) as a potential new capability, with a view to create an increased awareness and trigger further developments within the Alliance. The resulting MUS Study, published in November 2009, was then forwarded for endorsement by ACT, to the International Military Staff (IMS). Following this first document, CJOS COE has produced the attached Guidance document building on the initial study and aiming at supporting NATO MUS capability development.