In one of the most comprehensive studies of recent research on the health effects of recreational and therapeutic cannabis use, a new report from the National Academies of Sciences, Engineering, and Medicine offers a rigorous review of relevant scientific research published since 1999. This report summarizes the current state of evidence regarding what is known about the health impacts of cannabis and cannabis-derived products, including effects related to therapeutic uses of cannabis and potential health risks related to certain cancers, diseases, mental health disorders, and injuries. Areas in need of additional research and current barriers to conducting cannabis research are also covered in this comprehensive report.