The Guinea Current Large Marine Ecosystem (GCLME) which is one of the world's most productive marine areas include the Exclusive Economic Zones (EEZ) of sixteen countries, such as Angola, Democratic Republic of Congo and Sierra Leone. The area is an important global region of marine biological diversity supporting the livelihood of approximately 40% of the region's 280 million people living in the coastal areas. However, despite its resources and support to livelihood systems, the GCLME is facing a lot of challenging problems, including population explosion and urbanisation, fisheries depletion, water pollution, public health amongst others as it will be discussed in this article. The GEF project “combating living resources depletion and coastal area degradation in the Guinea Current Large Marine Ecosystem through ecosystem-based regional actions” implemented by UNIDO aims to reverse these trends and to achieve long-term development goals. These include restore degraded habitats and reduce land and ship-based pollution by establishing a regional management framework for sustainable use of living and non-living resources in the GCLME, through an economic valuation of ecosystems.