It is an incredible honor and privilege to follow in the footsteps of an individual who had a profound infl uence on the course of history and the fi eld of systems engineering. Since publication of the fi rst edition of this book, the fi eld of systems engineering has seen signifi cant advances, including a signifi cant increase in recognition of the discipline, as measured by the number of conferences, symposia, journals, articles, and books available on this crucial subject.
