Charles Ernest Overton’s 1901 monograph Studien aber die Narkose has become a scientific classic in a number of different fields. This book represents the first English translation, and in fact the first translation into any other language, of the original German work. In addition to* the edited translation, this volume contains introductory chapters by Keith Miller, Peter Winter and Leonard Firestone and myself. As editor, I have attempted above all else to ensure that the translation faithfully represents Overton’s ideas and data, while making the material readily understandable to the modem scientific reader. This has frequently required that extremely long sentences, common in turn-of the-century German but considered cumbersome today, be simplified into two or even three sentences. In addition, I have paid particular attention to the correct translation of scientific terms, and I accept complete responsibility for any inaccuracies in this area. Overton’s original contents list included headings and subheadings, but only a fraction of these appear in the original text. For the sake of clarity they have all been included in the body of the translated work. Also included is an index containing all chemicals mentioned in the book, along with their Chemical Abstracts System Registry Numbers for un ambiguous identification, a complete list of Overton’s publications (Appendix B), and a list of all biographical articles about Overton and articles dealing specifically with analyses of his data (Appendix C).