The term Unmanned Maritime Systems (UMS) refers to all systems, subsystems, associated components, vehicles, equipment and logistics for the operation of Unmanned Vehicles. These vehicles can be operated on the surface or underwater and may be remotely operated, partially or fully autonomous. The advancement of UMS technology to date has largely coincided with the requirements of the security and defence community, specifically for the challenges of Maritime Mine Countermeasures (MMCM). This has been facilitated by the availability of commercial off-the shelf products and the decreasing costs of electronic components. MMCM operations come with a high level of risk and have provided a successful test-bed for the use of autonomous systems. However, the growing tendency is that UMScan move beyond the challenges of MMCM and can be incorporated into many other security applications, as well as commercial applications. The development and adoption of new technology is often driven by an external threat. The rising incidence of terrorism, cross-border disputes, and conflicts have increased the need for enhanced border and maritime security across the globe. However, effective monitoring and protection of vast areas of marine interest is logistically difficult, expensive and sometimes dangerous to implement. The deployment of personnel, vessels and aircrafts for maritime applications requires intensive efforts and large operationalcosts. Nevertheless, it cannot provide sufficient coverage and resolution to ensure comprehensive and timely data availability forall areas and purposes. Unmanned marine data acquisition systems can help to overcome these limitations by providing timely and persistent data acquisition from the sea surface and beneath it. In this way, UMS can act as sentinels, enabling a more precise and selective approach in the deployment of conventional resources.As a result, many countries are adopting unmanned systems for improving the efficiency and reducing the costs of border and maritime patrolling operations, thereby increasing the demand for UMS. For instance, the Marine Corps in the U.S. are investing heavily on UMS for use in applications such as reconnaissance and maritime surveillance. EDA and ESA IAP are already collaborating in the domains of Remotely Piloted Aircraft Systems(RPAs) and Chemical, Biological, Radiological, Nuclear and explosives (CBRNe). The underlying rationale is the common interest of the two Agencies in developing and bringing to exploitation services integrating space and other terrestrial technologies in the specific identified domains.Similarly, the development of maritime services based on emerging technologies such as UMS, combined with the utilization of space, is considered of interest by EDA and ESA in terms of exploitation potential. The developed applications could be provided to authorities as Coastguards, Navies and other entities (e.g. Maritime Rescue Coordinating Centres ) to support services such as harbour and maritime corridors protection, demining operations at sea, Search and Rescue (SR) operations at sea,etc. Services addressing the private sector can also be elaborated. Following the trend of increased automation, combined with remote monitoring and control, it is expected that UMS will revolutionise the marine industry reducing production and operation costs. On this basis, ESA and EDA propose to jointly undertake a study, titled Maritime services based on Space and Unmanned Maritime Systems, with the objective of assessing the technical and economic viability of UMS based services exploiting at least one space asset.