This document provides a summary of a presentation on the risks of medical marijuana and marijuana legalization. It begins with disclosures from the presenters and outlines six learning objectives. It then discusses concerns that marijuana is addictive, especially for those who start using it early, and impacts adolescent brain development. The document notes the lack of evidence that marijuana is effective for the conditions it is claimed to treat. It also discusses the risks of increased diversion of marijuana to youth and greater social acceptance of marijuana use negatively impacting public health. The document concludes with messages on how to discuss these issues with the public.