Peace research is a relatively new field of study, but it has grown steadily over the past decades as university programs and think tanks were founded to deal with peace research. Reference works have been published to deal with certain aspects of the field: there are several directories of peace movements and historical guides to peace activism. In 1986, Oxford University Press published the most comprehensive reference work on peace to date, the four-volume World Encyclopedia of Peace, which has been updated this year as the Oxford International Encyclopedia of Peace (OIEP).

The main body of the OIEP consists of 850 entries, alphabetically arranged, on all aspects of peace, written by scholars from many disciplines. With any reference work containing this number of entries in an alphabetical arrangement, a good index is essential, and the editors have provided an extensive index plus a “topical outline of entries,” which groups the entries into broad categories such as “World Religions and Peace” and “Contemporary Conflicts, Crises, and Threats to Peace.” There is also a chronology of peace in history, a twenty-page timeline of important milestones in peace history, and a selection of one hundred key peace documents, mostly from the last one hundred years.

The editors have decided to limit the number of biographical entries and entries on specific organizations, opting instead to discuss their contributions in more general articles. Roughly 10 percent of the entries are for individual peace leaders or researchers, emphasizing “their ideas and contributions to peace and nonviolence and the evolution of the field” (xxviii). These range from Gandhi, Einstein, and Woodrow Wilson to lesser-known figures such as Dorothy Day, cofounder of the Catholic Worker movement. The majority of the entries, and the more extensive ones, focus on broader topics, such as “Arms Control and Disarmament,” “Conscientious Objection,” “Feminist Eco-Pacifism,” and “Early Warning of Hostilities.” The editors have taken a very broad view of peace studies in this work; many articles might strike the user as more pertinent to other fields, particularly those dealing with racial or economic inequality and environmental sustainability.

For larger reference collections, especially college and university libraries supporting a curriculum in peace studies, this is a reasonably priced and very comprehensive resource that brings peace research into the post 9/11 era. It is less than half the price of Elsevier’s three-volume Encyclopedia of Violence, Peace and Conflict (Elsevier, 2008), which covers all aspects of peace, aggression, warfare, and violence in lengthier entries on broader themes such as “Economic Causes of War and Peace” or “Conflict Management and Resolution.”

Smaller libraries with limited reference budgets, however, should take into account the extraordinarily multidisciplinary nature of peace studies. Much of the content of this work will also be covered in reference sources in sociology, political science, philosophy, history, or religious studies. For instance, the OIEP has two entries dealing with Quaker pacifism; there is nothing wrong with these entries but most libraries that would be considering this title will also have reference works in religion and in American history that cover the same material. The more theoretical concepts might also be covered in works like the New Dictionary of the History of Ideas, edited by Horowitz (Thomson Gale, 2005). The coverage of individuals and organizations might be duplicated in reference works specific to peace movements, such as directories of peace organizations. And finally, one of the ironies of any reference work about peace is that there might be overlap with reference works on war, as the two subjects are irrevocably interrelated.