Supporting Implementation of Maritime Spatial Planning in the Celtic Seas (SIMCelt) is a two-year project that aims to enhance cross-border cooperation between Member States on the implementation of the Marine Spatial Planning Directive (MSP). MSP is broadly defined as a process by which . . . Member States authorities analyse and organise human activities in marine areas to achieve ecological, economic and social objectives. Comprising a mix of governmental authorities and academic institutes, planners and researchers, from Ireland, France and the UK, SIMCelt aims to develop a suite of practitioner focussed, ecosystem-based tools to assess the current and future spatial demands and collective environmental pressures, of traditional and emerging maritime sectors. Addressing effective strategic and jurisdictional barriers, SIMCelt also aims to enhance transnational co-operation on the management of collective pressures to ensure sustainable use of marine resources and support the development of individual national maritime spatial plans that are coherent across the entire Celtic Seas region.