The recent Bubble and its crash caused severe difficult problems to many local municipalities. Governments of suburban areas were required to remake their future planning and want to know the basic future trends of the local economies. The purpose of this study is to construct a model of a suburban city and use it to forecast basic tendencies of its local economy. The results will be useful for the long-run planning of the suburban city government. We will present an econometric model for Mitaka City to describe her basic social-economic system, emphasizing her relations with the economy of Japan and the Tokyo Metropolis. Mitaka City has been a typical bed-town of the Tokyo Metropolitan Area for decades. In recent years, however, the social structure of Mitaka City is changing from a bed town to a commercial district. The model will consist of 43 equations with annual data for 1970-1991. The equations are divided into five or six blocks, which are: demographics, industrial activities, land uses and land prices, households, public sector and others. We will forecast several conditional cases up to 2010 assuming reasonable trends for Japan and the Tokyo CBD and discuss some policy implications.