This article examines collaborative environmental governance under authoritarian political structures. Building on the theoretical frame of authoritarian environmentalism, it peruses fieldwork material collected during 2009–2019 to determine the most prominent features of recent collaborative governance efforts in the field of water management in Vietnam, a historically seasonal flooding-dependent country. A key feature is technocratisation, where top-down management structures and practices prioritise technocratic solutions to environmental challenges over deliberation, awareness raising, and integration of local knowledge. Another equally important feature is authoritarian intensification, by which increasingly complex environmental management functions, coupled with the state’s determination to retain political control, reinforce authoritarian governance. We jointly refer to these features as captured collaboration, signifying a strong authoritarian regime dominance in both vertical and horizontal relations of environmental governance. However, while captured collaboration still appears to be a defining collaborative characteristic, the article acknowledges rising calls for deliberative government in Vietnamese society. This is particularly outspoken in relation to the highly contested issues of hydropower construction and enhanced floods, debates that simultaneously have paved the way for a burgeoning, though much delayed, paradigm shift.