This paper examines effectiveness of a regulatory enforcement organization (Major industrial Accident Prevention Center, MAPC), and a grading system for implementation of the Process Safety Management (PSM) regulation in Korea. A lot of chemical installations have been built in Korea since the 1960s. The frequent occurrence of major industrial accidents had made people's concerns grow. The Korean government enacted PSM regulations in 1996 in order to curb these accidents. However, a key question is how to make sure companies comply with the PSM regulations. In order to improve company' compliance with PSM regulations the Ministry of Employment and Labor (MOEL) responsible for the regulation introduced a grading management system in 2001 and then established special supervisory centers for enforcement of PSM regulations in 2005. This paper reviews the role and effectiveness of the system in term of PSM enforcement. The author found that the grade-based approach has encouraged employers to implement the requirements of the PSM regulations. MAPCs play an effective role in enhancing enforcement performance. Although the more chemical plants have been established in Korea, the fewer major industrial accidents have occurred since the introduction of the system. The results may be useful for the policy maker to build an effective and efficient enforcement system. (C) 2013 Elsevier Ltd. All rights reserved.