Finally, water boundaries cut across places in terms of cities (i.e. when concerning more municipalities in a metropolitan area) or hinterland (i.e. the surrounding environment, rural areas and watersheds, which sustain the major bulk of water demand from cities and where the actual sources of water are often located). Particular emphasis is put on the most prominent governance mechanisms that can foster effectiveness, efficiency and inclusiveness of urban water governance building on the OECD Principles on Water Governance (OECD, 2015c). They relate to vertical and horizontal coordination across policies, dedicated metropolitan arrangements and rural-urban partnerships (co-ordination across places), and stakeholder engagement (co-ordination across people).