When the six of us gathered to start planning for what was to be the Third Edition of Physiology of Membrane Disorders, it was clear that since 1986, when the Second Edition appeared, the field had experienced the dawning of a new era dominated by a change in focus from phenomenology to underlying mechanisms propelled by the power of molecular biology. In 1985, detailed molecular information was available for only three membrane transporters: the lac permease, bacterial rhodopsin, and the acetylcholine receptor. During the decade that has since elapsed, almost all of the major ion channels...