The most recent edition of Chemistry and Biology (Volume 18, Issue 5, May 2011) includes a feature article by Chandra Shekhar entitled “Mixed Signals: Cannabinoid System Offers New Therapeutic Possibilities As Well As Challenges” on the history, promise, and challenge of medical marijuana research. The article briefly outlines the history of cannabis research, and explains how the marijuana plant has been the key to one of the most significant medical discoveries of the last century: the endocannabinoid system. While private companies and government agencies have invested a great deal in developing medicines based on isolated and synthetic versions of the active chemicals in the marijuana plant, research on the safety and effectiveness of the marijuana plant itself still lags behind. The article explains how naturally-occurring cannabinoids help regulate some of the most important biological functions, and how modern researchers—including MAPS—are trying to learn which delivery systems and which cannabinoid combinations work best for which conditions.