この分野の定番レファレンスの11年ぶりの新版。100以上の新規・改訂項目を含む、約500項目（平均4000語）の充実した解説。With its initial publication in 1978, Bioethics became the first reference to focus solely on a then burgeoning field, in effect helping to define the discipline. The fourth edition offers hundreds of revisions or addenda to entries from previous editions as well as over 100 new or rewritten entries on topics such as key cases in bioethics, the human biome, genetically modified foods, emergency preparedness and response, social justice, sustainability, chemical warfare and torture, among many others.