The sustainable management of Blue Growth is an urgent issue for coastal states. Marine industries have rapidly expanded over the last two decades and this is projected to continue with the European Green Deal and post-COVID economic recovery policies. The intensification of Blue Growth could have adverse socio-ecological implications and must, therefore, be managed in terms of sustainability, natural resource boundaries, and coastal community well-being. Manging Blue Growth in a sustainable manner however, is challenging due to the longstanding inefficiencies and inertia of existing marine governance regimes. Adopting a transitions approach has been advanced as a way of steering regime change so that it is not inhibited by these persistent problems. This paper reports on four case studies that adopt transitions thinking and use the multi-level perspective as a broad analytical framework through which to understand institutional dynamics, drivers and responses within core marine sectors. Our case studies analysis reveals several significant pressures for regime change within key marine sectors. These pressures need to be addressed through the adoption of a transition management approach. By adopting this approach and engaging key stakeholders, national and EU marine governance authorities can develop sustainable Blue Growth pathways that minimise the impact of continued growth on communities and the marine environment, maximising the implementation of sustainable practices and addressing issues such as biodiversity loss and climate change.