Heterocyclic Chemistry is of the utmost practical and theoretical importance. Heterocyclic compounds are used in pharmaceuticals, dyes, pesticides, herbicides, plastics, and for many other purposes. The industries producing and researching into these products providing employment for a large fraction of organic chemists. On the theoretical side, heterocyclic chemistry provide a host of interesting concepts and structures. The subject is often deprived of the importance it deserves. It is possible to attend graduate school of some of the most prestigious universities without ever having attended a lecture course dealing specifically with heterocyclic chemistry. The series Advances in heterocyclic Chemistry was commenced in 1963 to attempt to provide a medium in which up-to-date results in the subject could rapidly be presented to a wide audience. The series has aimed to make available to graduate students and research workers in academic and industrial laboratories up-to-date reviews on wide variety of heterocyclic topics. Over the past 40 years 84 volumes of the series have been published and together they form a very substantial database covering wide areas of heterocyclic chemistry. Together with "Comprehensive Heterocyclic Chemistry" of which the first edition was published in 1985 and the 2nd in 1999 we now provide vast amounts of information on a subject which continues to gain in importance and to expand.