Preface. (T. Teramoto). 1. Motivation of the Project Research and a Hypothetical Circulation Model Presented Prior to the Research (T. Teramoto). 2. Structure of Subsurface Water Circulation and Associated Distribution of Water Properties. Deep Water Properties and Circulation in the Western North Pacific (M. Kawabe). Density Field along 12°N and 13°N in the Philippine Sea (K. Uehara, K. Taira, A. Masuda). Abyssal Boundary Current along the Northwestern Perimeter of the Philippine Basin (M. Chaen et al.). Deep Circulation in the Shikoku Basin Measured with the SOFAR Floats (K. Taira, D. Yanagimoto). 3. Circulation and Mixing of Water as Deduced from Distribution of Chemical Tracers. Chemistry and the Oceans: An Overview (Y. Nozaki). Philippine Sea Abyssal Waters in the Northwestern Pacific: Characterization from Tracer-Tracer Diagrams (T. Gamo). Dynamics of the Japan Sea Deep Water Studied with Chemical and Radiochemical Tracers (S. Tsunogai et al.). Instrumental Development for Measurement of Phosphate in Seawater and Some Discussion of Nutrient Distributions in the North Pacific (K. Fujiwara, H. Tsubota). Actinium-227: A Steady State Tracer for the Deep-sea Basin-wide Circulation and Mixing Studies (Y. Nozaki). Distributions and Mass-balance of 239,240Pu and 137Cs in the Northern North Pacific (Y. Nagaya, K. Nakamura). Trace Metals in the North Pacific - Recent Development of Clean Techniques and their Applications to Ocean Chemistry (H. Tsubota, S. Nakamura, K. Shitashima). Distribution of Dissolved Organic Nitrogen in the North Pacific Ocean (Y. Maita, M. Yanada). Determination of Some Oxyacid Elements and Manganese in Seawater and their Distributions in Some Unique Environments of the North Pacific (E. Nakayama, Y. Sohrin, K. Isshiki). 4. Vertical Flux of Chemical Substances and their Behaviours in the Deep Oceans. Seasonal Variation of Lithogenic Flux in Japan Trench Continental Slope Measured by Sediment Trap (S. Noriki et al.). Vertical Fluxes of Organic Materials in the Northern North West Pacific and Breid Bay, Antarctica, with Special Reference in the Effect of Phytoplankton Bloom (N. Handa, T. Nakatsuka). Organic Composition of Sinking Particles (JT-01) in Japan Trench as Revealed by Pyrolysis Gas Chromatography/Mass Spectrometry (R. Ishiwatari et al.). 5. Modelling of Subsurface Water Circulation and Associated Dynamical Processes. Numerical Modelling of the Philippine Sea (M. Kubota). The Occurrence of Vacillation in a Model Ocean Driven by Wind, Heat and Salinity Flux (K. Takeuchi, Y. Kashino). Modelling of Western Pacific Abyssal Circulation - Preliminary Experiment (N. Suginohara, S. Aoki, M. Nakata). Diagnostic Approaches on Deep Ocean Circulation (N. Imasato et al.). Laboratory Experiments of Dense Water Descending on Continental Slope (Y. Nagata et al.). 6. Development of Acoustic Technology for Ocean Measurement. Target Parameter Estimation by Linear-Period Modulated Signal (W. Mitsuhashi, H. Mochizuki). A Low Frequency Underwater Sound Source and Control Technique of Transducer Directivity (H. Hachiya, M. Okujima). Development of Multipaths Inverted Echosounder (T. Takeuchi, K. Taira).