Soda, O., a head investigator, theoretically analyzed the history of the rural-urban relationships, based on the field research. Main results of analysis are as follows.
It is generally considered that the country and the city stand in opposition and complications. However, both of the country and the city are combined each other with supplements. In facts, medium size of country cities and rural areas surrounding them became impoverished through the concentation of industries and population to big cities, especially the Tokyo zone, while about half of urban population wish to move to local zones. In the country, it is getting bigger to secure stable parttime jobs and to enjoy convinience of life as in the city. On the while, city dwellers are seeking for the life with full of green and nature, wide house or comfort as in the country, These requests from both sides should be attained by the generation of local cities. In Germany, decentralised land policy has been carried out since early times on the such point of view. Soda made clear its policy, and insisted that regional policy in Japan ought to direct decentralised structure of the region like comb.
Ikegami, K., a investigator, focused on the new usage of water between rural and urban societies. Ikegami insists as follows.
In many cases, water use of agriculture competes with that of industry and domestic use. However, as urban societies lose nature, urban dwellers desire to conserve water facilities of agriculture in the city. They play roles as free space, drainage stored, buffer of landscape and maintenance of water eco-system. Therefore, it is one direction towards co-existence of rural and urban societies to reuse water facilities of agriculture as "commons".