In recent years, the history of electroconvulsive therapy (ECT) has received renewed attention from historical researchers, who have published thorough monographs and articles on the subject of ECT. In these studies, however, one of the important events in the history of ECT has been overlooked: the lectures by Cerletti and Bini at the Third International Neurological Congress in Copenhagen. The lectures at the congress were the first presentation of ECT before a large international audience and became the impetus to the first Danish ECT trials. The first part of this article outlines the events of the neurological congress in 1939 and provides a translation of the paper presented by Bini at the congress. In the last part of the article, the history of ECT in Denmark is summarized.