More than 115,000 copies of the various editions of this book have been sold. The secret of this success lies partly in the fact that the book can be readily carried in the coat pocket, it is flexible, good looking, does not appear crowded, and it contains a summary of the most recent treatment of practically all the diseases. In this revision there begins on page 744 a summary of the recent treatment of syphilis as described in a series of special articles published in The Journal of the American Medical Association last year. Some additional new material has been added and some methods that have become obsolete have been deleted. The usefulness of this book has been proved by its wide popularity, and the new edition maintains the high standard set by its predecessors.