Cannabis has been used as medicine for 4,000 years. Now, with the majority of states legalizing medical marijuana, the U.S. is discovering this plant's full potential. Marijuana: The Medical Movement, the new Special Edition from the editors of TIME reveals the science behind marijuana's medical uses and explains why it may prove valuable for treating a wide range of conditions, including epilepsy, nausea in cancer and AIDS patients, IBS, nerve pain, rheumatoid arthritis and even Alzheimer's. It also shows promise as a substitute for opioids in managing pain. Legislation has hampered research, however. This edition covers the healing power of marijuana, how to keep your children safe, navigating the buying process in addition to exploring the pros and cons of legalization, and shares stories of researchers, patients helped by pot use, and medical experts, as well as the full history of the legalization movement, which is favored by 90 percent of all Americans. Learn more about the history of marijuana as medicine, where it is today and what's to come in the future, in Marijuana: The Medical Movement.