This consultancy aims to support water resources management and planning in South Sudan and the Nile basin through an improved understanding of the Sudd wetland; with a focus on its state; its ecosystem services; including for livelihoods and freshwater biodiversity; and the multiple pressures it faces. The specific objectives of this assignment are: 1. Synthesize data on the extent; characteristics; and state of the Sudd wetland; including its connection with transboundary surface and groundwater flows. 2. Assess and map the ecosystem services provided by the Sudd wetland at local and regional scales. 3. Pilot innovative monitoring approaches to collect data on freshwater biodiversity that depends on these ecosystem services. 4. Assess and map the impact of multiple pressures; such as climate change; land-use change; upstream diversions; pollution; on the Sudd wetland at present and in the future. Identify the main pressures responsible for the recent observed changes in the extent of the Sudd wetlands. 5. Develop recommendations and a roadmap to address identified pressures; fill knowledge gaps and enhance the contribution of the Sudd wetland to economic development and water security in South Sudan.