The Congo Basin, the second-largest tropical forest in the world, is vital to global ecological balance. This chapter explores its ecosystem functions and services, highlighting the immensity of its contribution through: (i) global climate regulation services by storing large amounts of carbon from plants. The region also plays a significant role in regulating water cycles; (ii) provisioning services by supplying numerous direct resources: wood, nontimber forest products and food for the region’s populations; (iii) supporting services, including soil formation, pollination and nutrient cycling, which are fundamental to other services and are maintained due to the exceptional biodiversity of the Congo Basin, which is the driving force behind them; (iv) cultural services for humanity in general, based on the immense spiritual, recreational and aesthetic value of the region’s rich biodiversity, which offers opportunities for tourism and scientific research. However, the Congo Basin faces enormous challenges related to human activities and economic pressures, which threaten its ability to provide vital services. Analysis of available data highlights the inadequacy and sometimes total absence of scientific data that could guide local and regional policies on sustainable development in the Congo Basin. Urgent and substantial investment in research is essential for the optimal use of the region’s natural resources.