Aquaculture is one of the most diverse food-producing industries and is suggested as a key solution to a growing global food demand. It has been argued that aquaculture has the potential to expand sustainably in most parts of the world, especially in the EU where consumption far out weighs production. This positive view surrounding aquaculture’s growth emphasizes its positive social and ecological effects. These include the generation of rural employment opportunities and the production of nutrient-dense food with negligible or even beneficial environmental effects (e.g. nutrient sequestration). However, for the industry to fulfil this potential, it needs informed governance structures and policies about social-ecological systems that are sensitive to local issues and conditions but also linked to the wider transnational/global context. This thesis provides empirical insight into how different levels of governance and policy interact and the ‘sustainability aquaculture development’ that different actors advocate. By using the Social-Ecological Systems (SES) approach as the theoretical foundation, combined with discourse and policy analyses, this thesis delves into how sustainability is framed in different aquaculture governance settings to give nuanced insights into varied sustainability discourses. This includes examining some of the most influential governing actors in the global North, ranging from intergovernmental organizations (IGOs) like the EU and UN to states and certification organizations.

Based on academic and international governing goals for expanding aquaculture sustainably through multi-stakeholder engagements, and the rapid expansion of Atlantic salmon production, this thesis analyzes how alternative influential governance regimes, like certification programs, compare in terms of environmental stringency with the national regulatory standards of the largest salmon-producing states. One region of interest in this thesis is the Nordics where aquaculture production is unevenly distributed. Norway is one of the most prominent global aquaculture production countries; other states such as Iceland are growing rapidly while countries around the Baltic Sea have very little production. Aquaculture in the Nordics is mostly centered around resource-intensive species with a high market value like Atlantic salmon. Continuing with the ambition to use multi-stakeholder engagements, this thesis also provides empirical insight into how policies and legislation are formed to promote aquaculture. Finally, based on global and regional recognition that food production needs to decrease its dependence on antibiotics, this thesis looks at how some of the most impactful aquaculture markets globally regulate antibiotics usage in aquaculture operations.

This thesis contributes by developing a conceptual framework to examine how different aspects of sustainability are aspired to and pursued in different aquaculture governance arrangements and settings. Through the application of this framework, the thesis develops critical insights into how governing actors frame sustainable aquaculture, identifying dissonances and synergies between international and national ambitions and making suggestions for how aquaculture sustainability can be improved.