The Eleventh World Congress of the International Society for Heart Re search 1983 provided an opportunity to review some of the growing points in our knowledge of the structure and function of the myocardium. Those at the meeting will recall how London suddenly went tropical. Yet aseries of scintillating reviews held over six hundred scientists captive in the lecture halls of Imperial College. There were sessions on nuclear magnetic reso nance, the molecular basis of electrophysiology, calmodulin, protein syn thesis and degradation, oxygen free radicals, the structural components of the myocyte, sarcolemmal sodium exchange, and the influence of lipids on membranes. Here we have gathered together, as quickly as possible, a number of the presentations of the speakers invited to the symposia. They give, we believe, a striking picture ofthe diversity oftechnology and scientific enquiry which underlies this immensely active domain of modern cardiology. If only our clinical colleagues were more aware of it! Peter Harris Philip A. Poole-Wilson London v Contents Evolution, Cardiac Failure, and Water Metabolism: Presidential Address … … … … … … .