The present volume originated from the workshop "Transduction in Biological Sys tems," held at the Marine Biological Station of the Universidad de Valparaiso, Mon temar, Chile, May 23-30, 1988, and contains contributions from most of the partici pants in the workshop. The title of both the workshop and the book reflects accurately the central theme discussed during several days of intense debate and profound intellectual exchange in the peaceful environment offered by the central coast of Chile. It was apparent that the workshop was a great success-a sentiment expressed by many seasoned attendees, some of whom dared opinions as strong as "It was the best ever." There is no single reason to explain why this workshop was so successful. Certainly instrumental was the incredible effort displayed by the Chilean Organizing Committee in selecting adequate facilities and in organizing social events that supplemented the scien tific sessions and provided an authentic fraternal environment for the participants. Equally important were the foreign participants, who enthusiastically gave of their time to take part in the event, and the students, who came from Chile as well as from several other Latin American countries, and who applied the necessary pressure in their repeated demands for scientific clarity, accuracy, and sincerity."