This book traces the development of the concept of abrogation (naskh) from its most basic form to the complex and multi-faceted doctrine it has become. The book also critiques the role of abrogation in rationalizing the view that not all the Qur'anic revelation has survived in the 'mushaf', i.e. the written record of the Qur'an. This role makes understanding abrogation an essential prerequisite for studying the history of the Qur'anic text. This book takes a practical approach by examining specific popular abrogation claims, such as the stoning penalty, the law on fighting non-Muslims, and on inheritance. It is the only modern study in English dedicated to the subject, and is a suitable reference work for both the expert and the general reader.