This paper explores the emergence of forms of ‘beyond farm’ assurance in the aquaculture sector, designed to increase the inclusion of smallholders and scale up environmental sustainability. The analysis reveals a ‘spectrum of assurance’, representing contrasting levels of trust in sustainable production and consumption. At one end of this spectrum attempts emerge to foster self-determined assurance models with internal verification that represent growing trust in the ability of subjects to organize sustainability improvements that extend beyond individual farms. The other, more dominant end of this spectrum, however, is populated with prescriptively and externally verified assurance models that demand high levels of control-driven assurance, demonstrating distrust in sustainability practices that extend beyond individual farms. The paper concludes that, to scale up sustainability, beyond farm assurance models must overcome the limitations of prescriptive assurance by finding fundamentally new ways of trusting farmers and their local counterparts in the global agro-food system.