The massive population concentration in Tokyo is continuing to grow under the weight of outmigration from Japanese prefectural capitals and provincial centers, while those capitals and centers, in turn, increase their populations by absorbing outmigration from small and medium-sized cities of 30,000–200,000 residents. Most such cities have tended to continually decline due to this outmigration, with the exception of satellite cities neighboring metropolitan areas. As the central functions of small and medium-sized cities are stagnating, the rural areas belonging to their tributary areas are not so active and also are depopulating.
Revitalization of Japan's small and medium-sized cities is therefore of keen importance for controlling the increasingly massive concentration of population in Tokyo. This, however, is a difficult problem, because these smaller cities have normally tended to decline because of their lack of competitive force against larger cities; a phenomenon persisting under the economic development since the country's modernization. Additionally, amid advancing globalization, many plants in small and medium-sized cities have shifted production overseas, also leaving the cities' shopping streets vacant and decaying as large retail stores from metropolitan capitals have invaded.
I am searching for regional policies to serve as guidance in preventing the decline of small and medium-sized cities. It is noticeable that in Germany most medium-sized cities (20,000–100,000 residents by the German standard) saw increasing populations in the periods of 1980–2010 and 2005–2010. I investigated the vitality of medium-sized German cities in hopes of finding regional policies that can be useful references for revitalizing Japan's small and medium-sized cities. But I concluded that such German cities face different conditions than Japan's small and medium-sized cities. Some of the German cities even house universities and headquarters of large firms. This is because of the low number of large cities and the lesser urban population in Germany; thus, the medium-sized cities do not face a conspicuous lack of competitive force against large and/or metropolitan cities. In this comparison, it is also difficult to dissipate the massive concentration already formed in metropolitan Tokyo.
However, we can take special note of two policies for controlling Tokyo's imbalance. The first is to implement the regional policy of moving head offices of large firms from the Tokyo metropolitan area to nonmetropolitan cities. However, it is difficult to spearhead movement into small and medium-sized cities other than prefectural capitals and provincial centers. The second policy is to introduce German Raumordnungspolitik (regional development policy) based on punktachsiales Entwicklungskonzept (development policy using central places and networks). This approach proposes regional planning by the central government-called teiju-jiritsuken-koso (promotion plan for settlement and independence) and renkei-chusutoshiken-koso (cooperative center urban plan) in Japanese-aimed at development of central cities that should be integrated and improved to serve as more active regional centers. Designated as medium-order centers (Mittelzentren) and high-order centers (Oberzentren) by German classification, these will to some extent be effective at revitalizing small and medium-sized cities, as well as their surrounding rural areas. Alternative regional policies must be adopted in Japan's isolated islands and mountainous areas.
This study examines the centrality and connectivity of major cities in Japanese urban system through relationships of corporate offices. After analysis of data concerning listed companies of five industrial sectors (textile products, chemicals, iron and steel, electric appliances, and transportation equipment) in 1985 and 2009, the following findings were obtained. Japanese inter-city network indicated that Tokyo, Osaka, and Nagoya had a significantly high degree of centrality. The degree of centralities of major core cities such as Sapporo, Sendai, Hiroshima, and Fukuoka were also high, but the disparity in their centralities was seen. Allocation patterns of branch offices ware different by sector, but branch arrangement patterns of company were quite similar within a same sector. Therefore, the inter-city relationships differ by sector.