Bergey's Manual is relied upon worldwide as it is the most comprehensive and authoritative work of its kind. Since publication of the first edition, the field of systematics has undergone revolutionary changes, driven by advances in molecular biology, leading to a classification of prokaryotes based on ribosomal sequencing. The list of named species has more than doubled since the first edition and descriptions of over 2000 new and realigned species will be included in the new edition along with more in depth ecological information about individual taxa and extensive introductory essays.