When was the last time you were on or near the sea? For most of us the answer will almost certainly be when we were enjoying leisure time. For the rest of the year most of us can remain fairly oblivious to the medium that shapes our topography, our climate, our history, our political make-up, our unique outlook, our economic well-being and our security. Yet the sea is far more important to us than we think. And even if it might not appear to mean a great deal to us now, it will in the future. It remains the world’s first and most important means of interconnectivity, and it is truly a global system. The sea and our relationship with it is changing and not in ways that are necessarily obvious.