Unity of doctrine is absolutely essential. This I set forth in my "Advice to Surgeons." In order to avoid the excess of operative measures which has been seen in recent wars, it was urgent to lay stress on the almost uniform conservatism of our present surgery, but a rapid, synthetic outline was not sufficient. It was necessary to complete it by information on the special aspect of the wounds we see, on their complications, and also by adequate details with regard to the best methods for us to follow. Therefore the present work became a necessary supplement.<br><br>It is intended both for beginners and also for those surgeons whose everyday practice - often specialized - has not allowed them to follow the advances made in military surgery.