For thousands of years the oceans have been highly prized and have providedus with efficient transport and a plentiful supply of food. Therefore, it seemsobvious that our modern society should continue to use the oceans andmaximize the benefits. There might be great treasures of valuable materials,new bio-compounds and endless energy. However society is reluctant tochange and resistant to new ideas so it is often found that new uses are notbeing accepted as quickly as their advocates would like. This book aims toshow that traditional uses of the sea can coexist alongside novel technology.Furthermore we present evidence that old and new ideas will complementeach other and the whole will be greater than the sum of the parts.The synthesis of established and growing industries at sea is coveredby the overarching label of the Blue Economy. Traditionally this has beensplit into two subsectors, the marine and maritime sectors. The maritimesector is easier to define because it relates specifically to the transport ofgoods, including ports and shipping and the supply chain that enables theseactivities. The marine sector by contrast includes industrial and businessactivity at sea, and those activities required to enable them. In this book wedefine the blue economy in a different way, and consider nine sectors whichare split according to their maturity. The establishedblue economysectors arefisheries, offshore oil and gas, shipping and shipbuilding, tourism and recre-ation, while the newblue growthsectors are aquaculture, blue biotechnology,seabed mining, wave and tidal energy, offshore wind energy. Other sectorsand sub-sectors do exist, but these nine give a broad overview of the whole.