Paris and Tokyo are; two world capitals which attract tourists, students, artists and foreign investors. To face their competitors, these two big cities are starting several urban planning projects. In Paris, as in Tokyo, construction takes place in several districts. However, the procedures for establishing city planning schemes and the process of their realization are very different in both countries. France is a decentralized country as proscribed the article 1 of the Constitution of 4 October 1958: «the organization of the Republic» is decentralized. Japan is, on the other hand, a very centralized country. The Japanese people find top-down organization suitable, while French people appreciate the participative approach. City planning is thus established at the local level in France, while the government and prefectures take the initiative in Japan, even if the elaboration of a local urban plan (Master plan) is attributed to the local self-governing body since 2000. Master plans have to reflect the opinions of the inhabitants. The public participates in Japan reluctantly, while in France, all the concerned persons can participate in all processes of elaboration of a local urban plan. In Japan, in spite of the centralization of power, certain powers are entrusted to private citizens. Since 1998, the examination of the application of a building permit can be delegated to a private organization. Since 2002, for certain measures, the act of expropriation can be also entrusted to a private citizen. Since 2003, city planning can also be proposed by property owners and private developers. The inconvenience created by the delegation of certain services to a private citizen is the mercantilism of the urban planning project. Several skyscrapers have been built in shopping districts located in city centers and even in residential zones where it is normally prohibited to build houses with more than 3 floors. The construction of a high-rise building often involves a dispute with neighborhoods wanting to preserve the landscape and the environment of their living area. In Paris, high-rise buildings are built on the outskirts of the city. Since 2011, the height limit permitted 50 meters. High-rise buildings increase total living space allowing more residence for students, foreign workers, travelers and underprivileged persons. Paris thus encourages the construction of local authority housing. In Tokyo, on the other hand, no new local authority housing has been built since 1999 on the pretext of a decrease in the population. In Tokyo and Kawasaki (a neighboring city to Tokyo), new housing has not been able to sell because of the economic crisis and the decrease in the younger population (20-30 years old). Without city planning for the inhabitants, the skyscrapers built everywhere spoil the landscape. Unfortunately, in Japan, the courts rarely protect the interests of the inhabitants. There are no administrative courts which are competent for any dispute with the administration. In Japan, a civil suit is filed. Judges often support the public authority. A way of appeal for the temporary suspension was created in 2004 with the aim of widening the protection of private interests. Judges can now investigate if the damage is not too grave to repair. They consider if the importance of the damage produced by the administrative decision is great enough to overtake the right of discretion or abuse of the administrative power. Nevertheless, in most cases, the administration wins at trial. Not only do the inhabitants usually lose their trial, but also many trials are simply refused by the court because of a lack of interest to act. As a consequence, several urban planning projects in the region in Tokyo region de not take into consideration the interest of the inhabitants.