This is a three-volume selection of classical papers by Michael Longuet-Higgins, who for many years has been a leading researcher in the fast-developing field of physical oceanography. Some of these papers were first published in scientific journals or in conference proceedings that are now difficult to access. All the papers are characterized by the novelty of their content, and the clarity of their style and exposition.The papers are quite varied in their approach. They range from basic theory and new computational methods to laboratory experiments and field observations. An overall feature is the frequent comparison between theory and experiment and the constant attention to practical applications.Among the many advances and achievements to be found in these three volumes are: the now generally accepted solution to the longstanding problem of how oceanic microseisms can be generated in deep water or near steep coastlines; a theoretical explanation of the strong drifting near the bottom in shallow water; the first introduction of a boundary-integral technique for calculating free surface flows; simple analytic expressions for the form and time-development of plunging breakers; and so on.The book will be of particular interest to advanced students in ocean engineering; also more generally to fluid dynamicists and physical oceanographers concerned with the interaction of the ocean with the atmosphere and with sandy shorelines.