Integrated multi-trophic aquaculture (IMTA), defined as the co-production of species at different trophic levels, is conceptuallyappealing. By utilising complementary functions of different species, it holds opportunities for lower environmental impact,higher productivity, and increased profitability in comparison with conventional monoculture. However, whether those advan-tages materialise in practice remains unclear. Here we review available life cycle assessment (LCA) and cost–benefit analysis(CBA) studies of IMTAs to further the current understanding of environmental and economic performance. We find that, overall,LCAs conclude that IMTAs investigated have not been able to deliver on environmental promises, while CBAs generally find thatIMTAs have both better financial performance and lower environmental externalities than monoculture equivalents. The mainreasons for these contrasting findings include the nature of the systems assessed so far—often theoretical or experimental set-upswith non-optimised designs—combined with methodological choices in assessments. The findings of the review thus suggestthat it is still unclear to what extent IMTA can deliver on its promises in practice, and that IMTA is no panacea for aquaculturebut requires careful design to be effective for its intended use. Integrating robust LCAs and CBAs early in the development phasecan help identify viable IMTA set-ups based on key drivers of environmental and economic performance and, in this way, min-imise the risks of misaligned practices. A first step towards realising the potential of IMTA is to carry out robust assessmentsthat avoid key mistakes in both LCAs and CBAs, to which end we provide hands-on recommendations for future assessments.
