The Encyclopedia of Genocide and Crimes Against Humanity tackles a difficult and often horrific subject. It looks at the worst, but also the best, of human behavior. The set is designed to offer the reader information about the barbarous acts that humans have perpetrated against each other throughout history, but also at the many and sometimes heroic efforts that have been made to understand, prevent, combat, and respond to such acts through law, politics, education, the arts, and sciences. The Encyclopedia is intended for general readers with a high school or college level education, although many professionals working in humanitarian and human rights organizations will find much here of use and interest to them.

World War II's Holocaust brought a new language into the world, including the word genocide. In response to the horrors of that event and other crimes committed in Europe and Asia, the international community conducted trials to prosecute and punish crimes against peace, crimes against humanity, and war crimes. These terms garnered better understanding as a result, although war crimes trials had precedents from earlier conflicts. After the Nuremberg and Tokyo trials, the first half of the twentieth century ended with states adopting an international treaty, the Convention for the Prosecution and Punishment of the Crime of Genocide, which outlawed efforts to destroy a people. Subsequent agreements have further identified and defined war crimes and crimes against humanity.

Genocide and crimes against humanity are not merely historical phenomena. It is estimated that more than 250 armed conflicts have occurred since World War II, with casualties numbering upwards of 170 million people. Some of these conflicts have been genocidal or involved war crimes and crimes against humanity, such as so-called ethnic cleansing and the use of rape as an instrument of war. Indeed, nearly all uses of armed force have involved issues discussed in the Encyclopedia. Massive human rights abuses committed by repressive regimes, such as kidnapping and disappearance of political opponents, massacres of minorities and systematic torture also fall within the rubric of crimes against humanity and, sadly, exist in contemporary society.

Efforts to prevent and respond to genocide and crimes against humanity are evident in the development of international criminal courts, peacekeeping, and humanitarian intervention by the United Nations, and the many educational programs and cinematic representations intended to raise public awareness of the problem. In addition, those countries throughout the world that are recovering from internal conflict or repression face the tasks of understanding the past, making appropriate redress to survivors or victims of abuse, and ensuring the accountability of those responsible for the commission of violent acts.

The topic is thus of vital importance and requires the involvement of a wide array of intellectual disciplines, professions, and skills. Historians, archaeologists, and anthropologists explain its global and temporal dimensions, identifying the past events that often led to current conflicts. Psychologists, philosophers, and theologians attempt to grapple with the reasons why human beings commit atrocities and seek to understand the responsive behavior of others, from collaboration through silence to active opposition. Lawyers and political scientists seek to construct institutions and legal structures that can impact human behavior, deterring genocide and crimes against humanity by designing effective and appropriate laws and punishment. Those in the arts educate and raise public awareness through film, music, painting, and writing. All of these disciplines appear in the Encyclopedia.

There are more than 350 entries in the Encyclopedia of Genocide and Crimes Against Humanity, arranged in alphabetical order for easy reference. In addition, an outline of contents at the beginning of volume one groups the entries thematically. The entries range in length from five hundred to five thousand words and concern historical and contemporary examples of genocide and crimes against humanity, individuals, groups, international institutions and law, theories and philosophy, prevention, prosecution, and cultural representations.

The set covers the ancient world to the present day and looks at all regions of the world. The editorial board affirmatively decided to include any event that has been publicly and reasonably debated as falling within the subject matter broadly viewed. Groups that have been the target of genocide or crimes against humanity are separately discussed, as are the known perpetrators. The various forms of reparation and redress available to victims and survivors are included, as are the courts and tribunals where the accused may be tried for their alleged offenses. Some entries describe the means used to incite public opinion toward hatred and genocidal acts, such as through advertising, radio broadcasts, and film. Short entries provide biographical information about key historical and contemporary figures, from Genghis Kahn to Simon Wiesenthal, while others describe important places such as Auschwitz and Srebrenica. Discussions of national and international policies during periods of genocide and crimes against humanity aim to provide readers with a wider perspective on the events reported.

The entries were written by experts, authorities in their respective fields. Like the topics they address, the authors come from countries throughout the world. As much as possible, the authors have used language that should be easily accessible to the public at large. The authors and editors have also attempted to be responsive to the sensitive nature of the topic, avoiding terms that may be offensive and noting where respected opinion is divided on the events or persons they describe. The result is a set of entries reflecting solid scholarship. A glossary of terms with which the reader might be unfamiliar appears at the end of the third volume, and each entry contains a bibliography to guide readers to further sources of information. Cross-references at the end of each entry refer to related topics.

The Encyclopedia contains historical images and contemporary photographs to illustrate the entries. Particularly for this topic, it is often difficult to visualize the reality of the events described. The editors have chosen the images carefully, not to shock but to provide further information and representation of the events and persons included.

At the end of the set, further material is included to assist the reader. In addition to the glossary, the concluding matter includes a filmography, primary source documents, and a comprehensive subject index. The primary documents may be of particular interest to those undertaking research in this field. The documents consist of key legal instruments, such as the Convention for the Prosecution and Punishment of the Crime of Genocide and the Rome Statute of the International Criminal Court, as well as several important judicial decisions.

The editorial board and contributors have all benefited from the editorial assistance given by individuals at Macmillan Reference USA, in particular Hélène Potter, Justine Ciovacco, and Shawn Corridor. Their dedication to the project and infinite capacity for work inspired everyone. We express our thanks to them and to the others who contributed by suggesting authors, entries, and materials for the set.