With a theme of Volcanism and Its Impact on Society, the November 2004 meeting of the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) held in Puc¿n, Chile, brought together experts to discuss many aspects of volcanology. The five-day IAVCEI meeting was the association's largest, attracting 940 participants from 44 countries. U.S. participants constituted one third. The meeting consisted of over 1100 abstracts presented in 12 theme sessions, and reflected a diversity of disciplines and techniques encompassed by volcanic studies.