Environmental Impact Assessment (EIA) is a kind of planning technique to seek ways to minimize environmental impact, a scheme to encourage sustainable development. With the launch of the Ministry of Environment in 1980, the EIA was introduced in Korea. Its full operation was initially driven by regulations on documenting EIA reports in 1981, which was piloted as a decision-making scheme where final decision were made at the development department after considering opinions suggested by the Ministry of Environment. At that time, dominance of the economic logic overwhelmed environ-friendly opinions, but thanks to the fourth revision of the Environmental Conservation Law in 1986, private projects came to be included on the EIA list. This was a turning point for the EIA to become a regulatory system. Local governments are also conducting the EIA regardless of the national-level EIA. In order to prevent and resolve increasingly severe environmental problems in Seoul in advance due to various construction projects, the Seoul Metropolitan Government, for the first time as a local government in Korea, legislated city decrees to introduce the EIA which has been underway from September 1, 2002. In particular, the Seoul government, unlike the Ministry of Environment, has included construction works on the list of evaluation projects, adopting the scoping and screen procedure scheme. In addition, complementing operational setbacks, the city government has revised and implemented decrees and enforcement laws on the Impact Assessment on Environment, Transportation and Disasters by shortening the consultation period, eliminating the submission of reports on construction, and expanding the waiver requirements in consultation over the reports. Therefore, development measures for the EIA scheme of the Seoul Metropolitan Government will be the target of the research. To that end, the up-to-date data of the Ministry of Environment, the Seoul government and local governments was collected, and latest materials from the EU, previous research and the Internet were gathered for analyses. By doing so, the flow of the EIA was reviewed, and the EIA schemes of local governments under the national EIA were analyzed. Furthermore, based on the Seoul government's recent data on the EIA based on the decrees, the background and legislation of the Seoul government's EIA were analyzed along with the developments for the environmental organizations. Setbacks were derived from the implementation period, evaluation procedures, consultation period and details of the EIA, and corresponding development measures were proposed.