This study fills a gap in the nexus debate by focusing on concrete actors and the nexus challenges they struggle with, instead of on abstract systems and the resource flows between sectors. Based on participatory, visual network mapping and focus group discussions, the paper illustrates three interdependent challenges of the water-energy-food nexus in the Upper Blue Nile in Ethiopia. First, it points to the central role of biomass-based energy resources and the need to balance national ambitions for hydropower and immediate energy needs for rural communities. Second, it identifies agricultural water management as a critical issue where linkages across sectors and scales need to be improved. Third, it highlights the need to strengthen actors working on environmental sustainability issues, and generating political support for their objectives, by making available evidence on the value of nature for development.