The Second Symposium on Numerical and Physical Aspects of Aerodynamic Flows was held at California State University, Long Beach, from 17 to 20 January 1983. Forty-eight papers were presented, including Keynote Lec­ tures by A. M. 0. Smith and J. N. Nielsen, in ten technical sessions which were supplemented and complemented by two Open Forum Sessions, involving a further sixteen technical presentations and a Panel Discussion on the "Identification of priorities for the development of calculation methods for aerodynamic bodies. " The Symposium was attended by 120 research workers from nine countries and, as in the First Symposium, provided a basis for research workers to communicate, to assess the present status of the subject and to formulate priorities for the future. In contrast to the First Symposium, the papers and discussion were focused more clearly on the subject of flows involving the interaction between viscous and inviscid regions and the calculation of pressure, velocity and temperature characteristics as a function of geometry, angle of attack and Mach number. Rather more than half the papers were concerned with two-dimensional configurations and the remainder with wings, missiles and ships. This volume presents a selection of the papers concerned with two­ dimensional flows and a review article specially prepared to provide essen­ tial background information and link the topics of the individual papers.