Eight years ago the Marine Corps published the first edition of Warfighting. Our intent was to describe my philosophy on warfighting, establish it as Marine Corps doctrine, and present it in an easy-to-read format. In the foreword to that manual, I charged every officer to read and reread the text, to understand it, and to take its message to heart. We have succeeded. Warfighting has stimulated discussion and debate from classrooms to wardrooms, training areas to combat zones. The philosophy contained in this publication has influenced our approach to every task we have undertaken. Fleet Marine Force Manual 1 stated, "War is both timeless and ever changing. While the basic nature of war is constant, the means and methods we use evolve continuously." Like war itself, our approach to warfighting must evolve. If we cease to refine, expand, and improve our profession, we risk becoming outdated, stagnant, and defeated. Marine Corps Doctrinal Publication 1 refines and expands our philosophy on warfighting, taking into account new thinking about the nature of war and the understanding gained through participation in extensive operations over the past decade. Read it, study it, take it to heart.