Abstract: "The recent surge in electronic nicotine delivery systems (ENDS) or electronic cigarette use among both adolescents and adults challenged tobacco regulatory frameworks worldwide. In this article, we review recent US Food and Drug Administration regulatory approaches to tobacco products, including attempts to regulate nicotine concentration and address youth use. We examine recent drives to promote a harm reduction approach in other product markets such as opioids, where the use of methadone and related therapies promote the public health. We describe the potential of a harm reduction framework for ENDS regulation based on tiered nicotine exposure standards coupled with risk-based product distribution controls that would enable ENDS products to meet the 'Appropriate for the Protection of the Public Health' standard required for tobacco product market entry. A harm reduction approach to ENDS regulation could help countries achieve the laudable public health goals of transitioning existing combustion cigarette users to ENDS products while preventing adolescent ENDS use and subsequent nicotine addiction".