Aquaculture is the world's fastest growing animal food producing sector. Although its overall performance is very good, it is unevenly spread geographically. In particular, the growth in most EU countries has been stagnating over the past 20 years despite repeated policy initiatives to launch new growth in the industry. The lack of production growth in EU aquaculture is often explained by strict environmental regulation and bureaucracy. In this article, we argue that an additional important element is an industry structure that limits the innovation and use of new technologies. Historically, farms have been small and often co-managed with larger agriculture production. However, to succeed in a market with global competition, technological innovation and sector-wide specialization, it is necessary to continuously increase productivity and induce investments in larger production facilities to take advantage of economies of scale. In Denmark, a structural change was ‘kicked off’ in 2005. In just 6 years, 30% of Danish production in freshwater has been reallocated to larger and more technologically advanced recirculation farms. Labour productivity has increased and the environmental impact per kilo of fish produced has been reduced, improving future prospects for aquaculture in Denmark and Europe.