The ICES Symposium on Acoustics in Fisheries and Aquatic Ecology (SAFAE) was held in Montpellier, France, from 10 to 14 June 2002. There were 303 participants from 37 countries, emphasizing the strongly international character of the meeting. This Symposium was the fifth organized by ICES in a series concerned with acoustics in fisheries and related fields. The first two were held in Bergen (1973 and 1982), the third in Seattle (1987), and the fourth in Aberdeen (1995; ICES Journal of Marine Science, Vol. 53, no. 2). To complete the historical picture, two symposia on the special problems of shallow-water acoustics should be mentioned, one held in London (1997) and one in Seattle (1999; Aquatic Living Resources, Vol. 13, no. 5). By 2002, however, it was seen that shallowwater, marine, and freshwater acoustics required a joint approach to problem-solving and the sharing of experience. It was therefore decided that this ICES Symposium would encompass all these applications within the general theme of acoustical methods for the study of aquatic biota and their exploitation. Organized under ICES auspices, the primary sponsors of the meeting were the Institut de Recherche pour le Developpement (IRD) and the Institut Francais de Recherche pour l’Exploitation de la Mer (IFREMER); cosponsors were the Acoustical Society of America, the UK Institute of Acoustics, the US National Marine Fisheries Service, and the Societe Francaise d’Acoustique. The coconveners were Francois Gerlotto (IRD) and Jacques Masse (IFREMER). They were assisted by a Scientific Steering Committee comprising Pablo Carrera (Spain), David Farmer (Canada), Masahiko Furusawa (Japan), D. Van Holliday (USA), William Karp (USA), Ole Arve Misund (Norway), John Simmonds (UK), and Will Tesler (Russia). The conference secretariat was efficiently organized by Laurence Vicens from the Centre Halieutique of the IRD, which provided much logistical support, as did IFREMER, especially through the editorial work of Brigitte Milcendeau. The main objectives of the Symposium were: to bring together scientists with diverse interests in fisheries and aquatic acoustics, covering a broad range of environments; to present their research in this rapidly evolving field; to review what can be achieved with new technology and theoretical approaches; and to consider future directions of study. There was a big response to the call for papers. The 256 abstracts submitted were allocated among the following ten theme sessions: