Book excerpt: Electronic cigarettes (E-cigarettes), also known as vape devices or by trade names such as JUUL, are handheld devices that aerosolize liquid commonly containing nicotine, humectants and flavorings. Used by 1 in 5 high school students in 2020, they are the most common tobacco product used by youth. E-cigarette use has been associated with a variety of health issues such as nicotine addiction, e-cigarette or vaping associated lung illness (EVALI), seizures, and increased risk of cardiovascular disease. This first-of-its-kind book begins with an introduction and background on the historical context of tobacco products. The next chapters provide an overview of the e-cigarette landscape and reviews the e-cigarette devices and solutions and the evolution of these products. This is followed by reviews of the health effects of e-cigarettes on users and non-users and includes recommendations for prevention and treatment of youth e-cigarette use. The last few chapters address the public health impact of e-cigarettes with a review of the evidence of e-cigarettes in smoking cessation. The book closes with policy and advocacy approaches and a resource page. E-cigarette and vape device use pose a public health crisis. This book contains succinct practical information and is a key reference for pediatricians as well as clinicians of all specialities. It also serves as a resource for health professionals, including tobacco dependence treatment providers and public health experts.