This book has its origins in a working document prepared by students at the École de l'Air, which trains all officers in the French Air Force. Its aim was to prepare them to be leaders. Naturally, it was conceivable to write THE good officer's handbook, to give them certainty and dispel their concerns. However, it is unlikely that THE manual would be the right answer. Because it would clearly not be the result of a scientific protocol establishing the general theory of command. It therefore seemed appropriate to compile a collection of personal accounts and documents on the act of command and the personality of the military leader. Because of its diversity - testimonies, reflections, legal standards, technical data - such a collection prevents the reader from learning recipes composed by someone else, probably in a position of hierarchical superiority. But the students at the Air Force Academy are not the only ones concerned; other military personnel and, no doubt, many civilians in positions of authority, may be interested in this concept, hence the idea of producing a book from this working document.