Volume 4 of the selected papers of Sir Hersch Lauterpacht concludes the systematic coverage, begun in volume 2, of his works on the Law of Peace. Volume 2 represented part I of these works on International Law in General and volume 3 moved on to parts II-VI covering statehood, territory and territorial jurisdiction, the individual, diplomatic intercourse and international organisation. Volume 4 now includes Lauterpacht's writings on state responsibility and treaties. Lauterpacht's important writing on the Law of Treaties is set basically in the framework he himself drew up from his work as rapporteur of the International Law Commission on that subject. The whole work continues the carefully organised presentation of a very distinguished international lawyer and only volume 5 now remains to be published.