Previous papers have set out the importance of maritime unmanned vehicle command and control in unlocking future maritime capability and the progress made under the Maritime Autonomous Platform Exploitation (MAPLE) project. The relentless pace of technological development is now seeing a number of unmanned systems readied for deployment and the Dstl lead MAPLE project actively involved in increasingly realistic and robust operational experimentation; and there are active plans for a minimum viable product implementation under Agile principles at sea in the coming year. As MAPLE enters a fifth phase, the ambition is a baseline capability that will enable the UK MOD to procure a full Maritime Autonomous Systems Command and Control system. This paper will talk to progress in developing and de-risking the technology and systems enablers and the plan to generate requirements documentation and Concepts of Operation, Use and Employment for a range of military tasks. It will also explain how the project is deepening understanding of the human factors implications of managing human machine teams alongside the conduct of existing warfare tasks. Continuing a long running MAPLE theme of end-to-end command and control, an overview will be given of how Phase 5 is developing the persistent architecture to address use of multiple MAPLE systems in a Force, and the use of effector systems deployed from unmanned systems. More widely, the paper will touch on how UK projects including MAPLE are at the forefront of an international effort to exploit maritime unmanned systems (MUS) and to secure interoperability and interchangeability, under a new NATO sponsored initiative.