This volume reproduces some important contributions to regional and urban economics made by Noboru Sakashita - one of the lead­ ing scholars in this field. Since graduation from the University of Tokyo, Noboru Sakashita has been teaching and advancing the re­ search at Hokkaido University, Tohoku University, Osaka University and the' University of Tsukuba. The career of Noboru Sakashita as a regional and urban econo­ mist started in 1965 when he visited the University of Pennsylvania's Regional Science Department as a Fulbright scholar. While staying there, he concentrated on research on regional science in a stimula­ tive atmosphere surrounded by Walter Isard, the founder of Region­ al Science, and Isard's young colleagues, all of who were full of pas­ sion for this newborn research field. The first two papers in this vo­ lume were written during his stay at the University of Pennsylvania. Since returning to Japan, he has been carrying out his own research activities as well as fostering many promising disciplines in the field of regional and urban economics. Of course, Noboru Sakashita is a world renowned famous scholar, presenting many influential papers at World Congress, North American and European Meetings of the Regional Science Association, and other conferences, and publishing many articles in respected journals. He was elected president of the Regional Science Association International for 1987-88, and served as the first president of the Applied Regional Science Conference from 1987 to 1989.