There is increasing support, in international legal theory and advocacy, for water governance approaches that go beyond the technocratic, and recognise the reciprocal relatedness of water peoples and water places. Such an approach may seem logical within certain Indigenous law and belief systems, but can Western legal frameworks become more ‘relational’? How can they evolve to be capable of meaningfully relating with Indigenous systems of law and governance for water? This article draws on a comprehensive survey of comparative legal developments affecting water across seven settler-colonial countries in Australasia and Latin America that attempt (or profess) to be relational. I critically evaluate these attempts against the ‘yardstick’ of relationality. In each jurisdiction there are unresolved calls for a social, cultural and constitutional transformation of some sort, in which Indigenous and environmental justice are key. The analysis here reveals the potential for constitutional law to drive relational water laws, although without place-based specificity and supporting institutions, resources and redistributions of power, constitutional approaches risk having little practical impact.