The Japanese government places great emphasis on ensuring the country's vitality in science and technology (S&T) and remaining at the forefront of global science. It is in this spirit that Japan uses its five-year basic S&T plans, the first of which was introduced in 1996, to guide research and development (R&D) promotion. This report summarizes the views of 55 leading researchers in the United States, the European Union, Switzerland, and Russia regarding the competitiveness of Japanese research in 25 fields in the life sciences, environmental science, information and communication technology, and nanotechnology and materials science. Their responses cover several topics, including how the quality of research in Japan in these fields ranks against the world's leaders, strengths and weaknesses in the Japanese research and education system, and suggestions of approaches, models, and mechanisms to increase excellence in Japanese research in these 25 fields and in expanding Japan's S&T capacity in general.