In 1994, within the frame of the ENCY 95 (European Nature Conservation Year) program, the Italian Navy set up a co-operative research program with universities and other research institutions to give logistic support and to apply its technologies to the study and protection of the marine environment. The project includes a research program on cetacean acoustics, mainly dealing with the two larger species in the Mediterranean Sea, the fin whale Balaenoptera physalus and the sperm whale Physeter macrocephalus (catodon). The Navy project will possibly lead to a major improvement in underwater acoustic research, as happened in the North Atlantic with the US Navy Project on "Dual Uses" of military technologies and should provide information relevant to the conservation of cetaceans in the Mediterranean Sea. Since 1990 a great effort has been made by the "Centro Interdisciplinare di Bioacustica'' (CIB) in the development of instruments to make underwater acoustic research feasible for small research groups with limited budgets and with auxiliary sailing vessels not specifically equipped. The instrumentation, which includes a towed hydrophone array made by Alenia-Elsag, tape recorders and computers to analyze and display in real-time the received sounds, has been extensively tested on several platforms and suited our requirements. At present the Navy provides auxiliary sailing vessels to host researchers and instruments for studying cetaceans. Recordings of biological sounds made independently by military vessels will be included in a special section of the Cetacean Sound Library created at the CIB, or comparison with previously stored recordings. In June 1995, during a co-operative cruise, the 'Alenia'' hydrophone was towed for 80 hours (out of 111 cruising hours). One sperm whale was acoustically tracked and continuously recorded for 7 hours. Seven fin whales were also sighted. The main goal for this first year was to collect information and literature, to test protocols for data interchange and to co-ordinate the efforts in the development of instruments and methodologies. In the near future ASW (Anti Submarine Warfare) underwater acoustic systems should be used to extensively study 5n whales and sperm whales to discover, understand and monitor their seasonal movements and behaviour in the Mediterranean Sea.