Margaret Chan is a prominent public health expert from Hong Kong. She served as the Director-General of the World Health Organization (WHO) from 2006 to 2017. During her tenure, she focused on global health issues, including infectious diseases and health system strengthening, and played a key role in responding to health emergencies. Before leading the WHO, Chan held various positions in the Hong Kong Department of Health and the WHO. She is known for her efforts in improving health policies and promoting health equity worldwide. Chan's work has significantly influenced global health initiatives and responses to public health challenges.