The editors of Stress, Trauma, and Substance Use have gathered a collection of innovative chapters written by cutting edge researchers that depict both the breadth of the relationships between stress, trauma, and substance use, as well as how closely these phenomena are all too often linked. Individually, the chapters in this volume present innovative conceptual models, original research findings, and recommendations to service providers that are applicable to a diverse body of individuals affected by a wide variety of stressful and/or traumatic experiences, such as HIV/AIDS, incarceration, homelessness, sexual assault, and other forms of trauma and violence in addition to substance use. Taken as a whole, the content of this text provides a window into the true nature of the multi-layered and interconnected relationship between stress, trauma, and substance use. The untangling of these relationships holds great promise for continued research that develops a better understanding of these phenomena and ultimately improves the lives of individuals touched by these experiences.This book was previously published as a special issue of Stress, Trauma, and Crisis: An International Journal.