The goal of the present handbook is to offer encouragement, examples, rationales and concrete advice on how to increase youth participation in substance use prevention, harnessing the insights of young people on the most important target group in prevention efforts: their peers. It is designed to enable all decision makers to capitalize on the power of youth participation, exploring the full potential of young people as a force for change. The guidance is aimed at leaders in charge of substance use prevention and health promotion efforts at the local, regional, national and international levels. The handbook provides an overview of youth participation and what role it might play in prevention. It seeks to convey the value of evidence-based prevention in building healthy and prosperous communities and societies, and the value of young people as important contributors to prevention efforts. By so doing, it seeks to contribute to the normalization of youth participation in prevention. One of its key objectives is to unravel the misconception that young people have limited capabilities to contribute to substance use prevention efforts. In addition to dismantling such misconceptions, which can lead to the hesitation to include youth in such efforts, it also seeks to raise caution against the possible undesired outcomes of involving youth merely for the sake of visibility and thereby contributing to an environment of tokenism.

Finally, it also seeks to address the misconception that merely being a young person and interested in being involved in substance use prevention is sufficient to achieve prevention outcomes. In this handbook, it is stressed that achieving purposeful, ethical youth participation requires education for all parties involved, not only on evidence-based prevention, but also on youth participation itself. Decision makers and professionals deserve capacity-building on how to generate meaningful participation among young people. Similarly, researchers could benefit from support and training on how to carry out research both with and for young people. It is equally important to ensure the education, training and development of the participating youth. Only sufficient guidance and other organizational support will enable young people to play a meaningful role in the process. Well-informed and well-trained policymakers, leaders and youth are a key component in ethically planning, implementing and evaluating effective substance use prevention interventions.