A report by Union for the Mediterranean - with the financial support of the Swedish International Development Cooperation Agency.
From the introduction:
The Blue Economy is “the set of human activities depending on the sea and/or underpinned by land-sea interactions in the context of sustainable development, and notably including industrial and service sectors such as aquaculture, fisheries, blue biotechnologies, coastal and maritime tourism, shipping, ship-building/repair, ports, ocean energy and marine renewable energy, including offshore wind, which are among the main traditional and emerging economic maritime sectors in the Mediterranean Sea basin”. .
UN Environment defines the Blue Economy as a "green economy in a blue world", since "a global transition to a low-carbon, resource-efficient Green Economy will not be possible unless the seas and oceans are a key part of these urgently needed transformations". .
The goal of the Blue Economy is therefore to face the global, environmental, economic and social crises of the last decades, looking at the ocean resources as development spaces that, used sustainably, may trigger economic prosperity. 
Since ancient times, the Mediterranean Sea has played a key role in the economy of coastal communities and States. Today, more than ever, the Blue Economy sectors are an important engine for the region's economy, with enormous potential for innovation and for sustainable and inclusive prosperity. The economic opportunities provided by the Mediterranean Sea are accompanied by an increasingly need for a management that is respectful of its ecosystems and is able to maintain and increase their value over time.
Sustainable conversion of economic sectors that have often adversely affected the health of ecosystems, such as fisheries and coastal tourism, as well as the development of new clean and technologically advanced activities – e.g. renewable energy –, represent important opportunities for innovation and employment for the benefit of all Mediterranean countries.
Close collaboration between all the Mediterranean countries and their stakeholders is a condition for realising a common objective: the sustainable use and conservation of our main common resource, the Mediterranean Sea.