Substance abuse has long been a serious public health problem around the world, and Hong Kong is no exception. On the invitation of Stanley Ho Centre for Emerging Infectious Diseases, Dr Robert Newman, Director of Baron Edmond de Rothschild Chemical Dependency Institute, New York, delivered a public lecture titling “International Drug Policy – Back to the Future” at CUHK. Dr Newman is also a professor of the Albert Einstein College of Medicine in New York. Thirty-five years ago, Dr Newman was a consultant to the Hong Kong Government on the treatment of heroin abuse. With the changing landscape of substance abuse, he shared his thoughts with Hong Kong again on what should constitute an effective strategy in public health context.