Environmental problems often outstrip the abilities of any single scientist to understand, much less address them. As a result, collaborations within, across, and beyond the environmental sciences are an increasingly important part of the environmental science landscape. Here, we explore an insufficiently recognized and particularly challenging barrier to collaborative environmental science: value pluralism, the presence of non-trivial differences in the values that collaborators bring to bear on project decisions. We argue that resolving the obstacles posed by value pluralism to collaborative (...) environmental science requires detecting and coordinating the underlying problematic value differences. We identify five ways that a team might coordinate their problematic value differences and argue that, whichever mode is adopted, it ought to be governed by participatory virtues, pragmatic resolve, and moral concern. Relying on our experiences with the Toolbox Dialogue Initiative, as well as with other dialogical approaches that support team inquiry, we defend the claim that philosophical dialogue among collaborators can go a long way towards helping teams of environmental scientists and fellow travelers detect their problematic value differences. Where dialogical approaches fare less well is in helping teams coordinate these differences. We close by describing several principles for augmenting philosophical dialogue with other methods, and we list several of these methods in an appendix with brief descriptions and links for further learning. Overall, the article makes three main contributions to the research collaboration and values in science literatures: It deepens our understanding of problematic value pluralism in team science; It provides actionable guidance and methods for improving values-oriented philosophical dialogue interventions; and It demonstrates one way of doing engaged philosophy. (shrink)