The aim of this volume is to present an up-to-date survey of our state of knowledge of the physical and dynamical processes involved in the Asian monsoon. Although traditionally the main emphasis has been on the study of the atmospheric component, it has been known for a long time that the oceans play a vitally important role in determining the occurrence of this spectacular seasonal event. A scientific study of this phenomenon must involve a detailed investigation of the dynamical processes which occur in both the atmosphere and the ocean, on time scales of up to at least a year and on spatial scales from a few hundred kilometres or so up to that of the global atmospheric and oceanic circulations. Such problems are of considerable intrinsic interest not only to meteorologists and oceanographers but also to fluid dynamicists in general, and the Joint IUTAM/IUGG International Symposium on Monsoon Dynamics, held in Delhi from 5 to 9 December 1977 had as its major aim the bringing together of all of these groups of scientists. This volume serves as a Proceedings of this symposium. An attempt has also been made in selecting and editing the contributions to present a coherent survey of each of the meteorological, oceanographic and hydrological aspects, and of their implications for weather forecasting and flood prediction. Some of the most recent observations are presented, including those which have become available from satellites.