Adverse drug reactions constitute a major public health problem. In recent years, serious safety issues arose with marketed drugs, and public outcry demanded better safety surveillance. Now regulatory focus is shifting to the active post-marketing safety surveillance. This paper provides an overview of the recent international initiatives of drug safety management especially focused on the US and Europe. The US Food and Drug Administration's (FDA) Sentinel Initiative is a long-term program designed to build and implement a national electronic system for monitoring the safety of FDA-approved drugs and other medical products. The Sentinel System will enable FDA to monitor the safety of medical products with the assistance of a wide array of collaborating institutions throughout the nation. The European Network of Centers for Pharmacoepidemiology and Pharmacovigilance is a collaborative scientific network coordinated by the European Medicines Agency and developed in collaboration with European experts in the fields of pharmacoepidemiology and pharmacovigilance. Its goal is to further strengthen the post-marketing monitoring of medicinal products in Europe by facilitating the conduct of multi-center, independent, post-authorization studies focusing on safety and on benefit-risk. Medicine is a global enterprise that demands worldwide standards for good drug safety practices. In the near future, we have to establish a Korean Sentinel System for active post-marketing safety surveillance to ensure the safety and effectiveness of drugs used in medical practice.