The thrust here is for those who want to know more than the answer to an exam question - an approach to disease diagnosis and treatment which emphasizes thoughtful consideration of alternatives, finding ones way through uncertainties and lack of knowledge. The annual seminar on which this volume is based has evolved into a forum for open discussion of puzzling questions - actually old questions in the light of new data. To me, the adventure of life is in recognizing the openendedness of all things. So you thought that a certain disease was a settled question? In medicine a "settled" question is a transient conclusion. Even the solutions to the so-called simplest problems have another side. Our aim this year was to air out concepts and conclusions about hypertension, fluid-electrolytes, and tubulopathies. The stars were Drs. Juan Rodriguez-Soriano, Alan Gruskin, and Donald Potter, along with Drs. Gustavo Gordillo, Ronald Kallen, and Antonia Novello as guest faculty. Local stars included Drs. Mary Jane Jesse, Jacques Bourgoignie, and Carlos Vaamonde. Their contributions added to those of the other faculty and registrants, coalesced into vibrant exchanges which are reproduced here for the reader's perusal.