The filoviruses (Lake Victoria marburgvirus and the ebolaviruses) are etiological agents of severe hemorrhagic fevers with extraordinary high case-fatality rates for humans, chimpanzees, gorillas, and probably other animals. This review summarizes in detail the contemporary knowledge of filoviruses and the diseases they cause. The entirety of the open literature on filoviruses, covering all major scientific and clinical fields, is referenced and summarized in this text, including most of the conference abstracts, book chapters, dissertations, government reports, patents, theses, and journal publications in many languages. For ease of retrieval by the reader, all references are cited with original titles in the original spelling, first author names, full journal titles, and issue numbers where possible. The text of this book and the accompanying reference resource will be updated in the future, and thus will provide a robust source of information for filovirologists, other virologists and scientists in general, clinicians, students, journalists, and biodefense professionals.