Under the auspices of the Tsunami Commission of the International Union of Geodesy and Geophysics and the International Coordination Group of the International Oceanographic Commission, the IUGGIIOC International Tsunami Symposium, TSUNAMI '93 (Sixteenth International Tsunami Symposium) was held in Wakayama, Olle of the most historical areas in the prevention of tsunami disasters in Japan, from 23 to 27 August, 1993 by the Organizing Committee of the Japan Society of Ovil Engineers, in commemoration of the International Decade for Natural Disaster Reduction. More than one hundred and fifty scientists, engineers and specialists specializing in tsunami research and mitigation of the disasters met from thirteen countries to exchange current information on technica1 advances and to discuss progress in the science. Over hundred and ten abstracts were submitted, most of which were excellent. It was specially agreed in this symposium that in the aftemoon of the third day a usual session for operational tsunami warning systems and plans for improvement is hdd, but three days for presentation and publication restrictions only permit the presentation of less than 78 papers.