Even in an increasingly polarized climate of global policy-making, the ideal of “sustainable development” retains currency across a remarkably broad swath of the political spectrum in debating alternative scenarios for the future. By adapting Weber's classic categories of value spheres and collective rationality, I distinguish contemporary approaches to operationalizing the concept of sustainability and elucidate the practical implications of each. For some, the social, ecological, and economic dimensions of sustainability are synergistic components of a single meaningful goal, pursued by either an overarching technique or a unifying ethic. In contrast to these unifying models, one may conclude that the dimensions of sustainable development invoke values that inevitably conflict in any complex social interaction to derive strategies for collective action. Framing the concept in such terms, as a dialogue of values, highlights the need to adapt social institutions to mediate value conflict at different scales, and points to opportunities for engaging development debates through applied research on comparative governance.