The document describes a regional WASH coordination model in West and Central Africa. It discusses establishing a regional space to improve humanitarian response efficiency through strengthening WASH coordination from the regional to country levels. The model involves conducting joint regional analysis of major humanitarian issues, defining regional strategies, and diffusing strategies through national coordination bodies. This includes strategies on undernutrition in the Sahel region and cholera outbreaks. The regional approach aims to harmonize response, facilitate information sharing and cross-border learning, and provide strategic guidance and funding support to national coordination. Challenges include the informal nature of regional coordination and need to build on strong national coordination.