In 1996 the International Committee for Taxonomy of Viruses (ICTV) recognized the name Nidovirales, as the formal name for Coronaviridae and A rteriviridae. In recognition of this change, and in response to the wishes of our colleagues we named this meeting for the first time "The International Symposium of Nidoviruses." The meeting in the wooded environment of Lake Harmony, Pennsylvania, provided a stimulating opportunity for assessing the progress made in the field since the last meeting in Segovia Spain in 1997. Over 150 scientists from academia and industry attended the meeting. The...