Toshi has a completely different concept from such administrative words as shi (city) and machi (town). "Urban area" is said to be the most appropriate translation for the concept of the Japanese word toshi. Many years ago&sbquo forms of habitation were called shuraku (communities). Shuraku could be divided into villages inhabited by people involved in industries directly related to the land and urbane communities inhabited by people involved in industries unrelated to the land. According to the scale of such urbane communities&sbquo those communities were divided into small-scale machi (town) and larger toshi. Since living styles were different&sbquo village society and urbane society used to be distinguished sociologically&sbquo but since those differences have disappeared&sbquo the two are no longer seen as contrasting concepts. This definitional shift can be verified by retroactively tracing the history of political control and forms of habitation. In modern times&sbquo functional differentiation of various toshi&sbquo have led to a diversity of designations&sbquo such as seisan toshi (manufacturing city)&sbquo koeki toshi (trading city)&sbquo shohi toshi (consumption city)&sbquo gakujutsu toshi (academic city)&sbquo and kanko toshi (tourist city). An area having the basic functions of toshi is considered to be a sogo toshi (general city)&sbquo and it has become common to view the area from the center of a toshi to a gradually formed urban center as toshi chi-iki (urban district)&sbquo and the area that complements the various urban activities as toshi ken (urban zone). In urban design&sbquo it has become necessary to design urban environments. A new theme that will determine the urban environment concerns what shape the urban structure—which is becoming densely information-oriented—should take. This has also emerged as a new issue in design. This is due to the problem of differentiation in community formats owing to information gaps&sbquo while mammoth cities form by the concentration of population and village society disappears due to rural depopulation. In addition to the evolution of urban communities&sbquo an appeal to civil awareness to preserve the urban environment and protect historical districts has been raised as a subject of environmental design. Toshi exists as the grand design of all these elements.