Abstract In this article, we examine oceans outcomes from the Third United Nations Conference on Sustainable Development (or Rio+20) in relation to how ocean problems and solutions were defined and by whom. We highlight the extent to which problem and solution definitions were shared among participants, in relation to three specific issues on the agenda at Rio+20: conservation and sustainable use of biodiversity in areas beyond national jurisdiction, small‐scale fisheries, and ocean acidification. We find that discussions about each of these issues reflect three challenges recognized as complicating oceans management: mismatches between ecological and governance scale, homogeneity among interest groups advocating for ocean conservation, and increased interest in both protection and exploitation of ocean resources. Overall, we found little evidence of constructive dialogue at Rio+20, where participants focused on advancing predefined positions, and we consider the implications of our analysis for ultimately addressing our three focal issues and for oceans management more generally.