The spatial structures created by the internal organization and activities of enterprises have become an important determinant of the composition of urban systems in advanced capitalist countries. In this, research, the author attempted to clarify Japan's urban system with respect to the development of intra-corporate branch networks, focusing on the 74 leading ci.ties(the prefectural capitals plus other cities with populations above 300, 000). The data were converted from the Establishment Census published by the Statistics Bureau of the Administrative Management and Coordination Agency, which classifies establishments into 10 major industries and 28 economic categories (Table 4), and by whether they are independent enterprises, headquarters or branch esatblishments (with the latter broken down by the location of the enterprise's headquarters). Employment total are given city by city for each category. From these data the author calculated the shares of totals employment in each city broken down by the location of the enterpriese's headquarters and the number of prefectures in which branches have been established (see a)-g) in Table 5).
The results of this analysis reveal the following: 1) The overall pattern of development of intra-corporate branch networks suggests that a national urban system has taken shape around a nucleus of enterprises based in the three largest metro-politan areas (Tokyo, Osaka and Nagoya <Aichi>).
The intra-corporate branch networks associated with enterprises based in Tokyo have developed on a truly nationwide basis (Figure 3). Analysis of the data reveals that the employment shares for branches of enterprises based in the three metropolitan areas average 30.8% for cities located within the metropolitan zone, 24.8% for cities located on the metropolitan fringe, and 16.5% for cities located in the provinces. In other words, the influence of the metropolitan areras is felt strongly even in the cities in provincial zone. There are also clear differences in the development of metropolitan-based intra-corporate branch networks within a provincial zone: employment shares range from an average of 25.1% for the core provincial cities (Sapporo, Sendai, Hiroshima, Fuku-oka), to 14.74 for prefectural capitals, and 13.2% for other lower-tier regions.
The intra-corporate branch networks of enterprises based in the core provincial cities and in quasi-core provincial cities (such as Kanazawa and Takamatsu) have in turn become important components of urban systems at the provincial level, taking in the prefectural capitals within each provincial block (Figures 1 and 5). In practice, many of these provincial enterprises may well be under the financial control of interests based not locally but in the three metropolitan areas, although for the moment the true extent of such indirect metropolitan influence must remain a matter for further research.
2) An investigation into the development of metropolitan-based intra-corporate branch networks by industry group and economic category reveals that within the metropolitan zone there is a prepon-derance of establishments engaged in local scale activities closely linked to daily life (especially establishments classified as retailers or service industry outlets) . On the metropolitan fringe, however, we find establishments engaged in manufacturing (especially of machinery) and in regional-scale business activities (including wholesaling and certain forms of retailing, especially large stores selling a wide range of products), while in the provinces we find establishments in industries which are organized on a national scale, such as machinery manufacture, wholesaling and insurance (Figures 7, 8 and 9).
