This book will fill a very large void in the scientific literature and it is quite certain that the volume will become the standard reference for those needing to have critical access to Alternaria literature and taxonomic information. There are many scientists, both research and regulatory, who are in desperate need of resources such as this book to facilitate routine identification. More than 1,100 published names are associated with taxa that must be considered in the Alternaria context. Of these, 276 species with validly published names are maintained here as currently identifiable; these are keyed in the main text of the volume. An additional 16 named taxa, although requiring expanded information and comparison, also are accepted. A few species that have been associated with the genus for years but which now are followed by a comprehensive list of all the nearly 1,200 names involved historically with Alternaria taxonomy in the period 1796-2007. Each name is listed with its source, type, and an opinion on its validity and taxonomic disposition. A host index to all accepted species is followed by a comprehensive list of literature cited and a general index. Within the context of the manual, 88 names are assigned to newly described species and genera and to taxa whose epithets appear in new combinations.