Rates of cannabis use continue to climb worldwide, reaching historic “highs” in some populations. While recent research has unveiled potential benefits of cannabis and its constituents, including cannabidiol (CBD) and Δ-9-tetrahydrocannabinol (THC), for treating certain medical conditions (e.g., seizure disorders, spasticity related to multiple sclerosis), emerging studies highlight potential risks—especially for vulnerable developing populations. In particular, cannabis may be harmful during periods of rapid brain development, such as during pregnancy and adolescence. This book draws on the latest scientific research to examine the intersection of cannabis use and neurodevelopment, providing a nuanced perspective on its risks and benefits. Topics include the foundational science of the endogenous cannabinoid system and its role in brain development, the impacts of prenatal cannabis exposure on early neurodevelopment, and the unique vulnerabilities of the adolescent brain to cannabis use. The book also explores psychiatric risks such as psychosis and suicidal ideation, as well as the influence of social and environmental factors like secondhand cannabis exposure and minority stress. Written for scientists, healthcare providers, policymakers, parents, and educators, this book equips readers with the knowledge to understand and navigate the complexities of cannabis use in developing populations, while fostering informed dialogue and evidence-based practice.