For centuries the low of the tides has fascinated mankind and it is only now that we are beginning to understand their importance to climate and life on Earth. In this interview based program we explore the tides and the forces that generate them. The equilibrium theory and the dynamic theory of tides are explained by marine experts and physicists, who specialize in tidal activity. They discuss why some regions have two tides per day and others just one, and the behaviour of tidal currents. This program is an excellent resource for students of geography, marine biology and marine physics at all levels.