Among the numerous books dealing with the Kellogg Pact, this study by an eminent historian closely connected with the efforts made in the direction of peace in the last decade, is bound to hold a leading place. The actual account of the negotiations is perhaps the least important part, though the author has added materially to our knowledge of the unofficial activities connected with the international discussions. The really significant part is the setting of the pact in the general problem of war and peace. Professor Shotwell's discussion of the nature of war and the inherent difficulties in the way of its abolition should help to clear up some current misconceptions. Of his analysis of the text of the pact itself little need be said, as this is bound to be more or less a matter of opinion. To some he may seem too optimistic, but his view is of importance as coming from a writer who is unusually well-informed.