Understanding and constructively using natural sound in the ocean has become of prime importance with the shift of emphasis to protecting the environment and exercising responsible global resource management which has followed the end of the Cold War. Especially now that we realise that marine mammals and other inhabitants of the oceans are threatened by our acoustic pollution of their environment, the use of natural sound as a non-intrusive remote sensing probe has become particularly germane. This was the first meeting on the subject since the fall of Soviet-Western barriers, and the proceedings include significant work from premier researchers in the former Soviet Union. It was also the first meeting which specifically addressed the new and exciting idea of using natural sound in applications for monitoring the marine environment. The proceedings include a number of papers on various aspects of this topic. Further new work on the basic physics of sound production and propagation is also included. This volume includes leading-edge work from the foremost researchers in the field, including Bill Carey, Lawrence Crum, Nikolai Dubrovskii, David Farmer, Brian Kerman, Bill Kuperman, Michael Longuet-Higgins, Hank Medwin, Ken Melville, A Prosperetti and many others.