One of the most familiar phenomena on the planet, water waves remain an elusive question for science. The way in which wind blows over water and causes waves is a very active area of research for applied mathematicians, as well as for oceanographers and engineers. The basic mechanisms are still a matter of controversy, although the use of modern techniques of asymptotic and non-linear analysis and large-scale computation, as well as experimental structures, are beginning to reveal the underlying mechanics. These studies are resulting in increasingly powerful methods of forecasting waves and...