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In addition to this Fast Company feature, Bill Breen also contribtes several Web Exclusives -- related articles that did not run in the magazine. Hortapharm CEO David Watson discusses what might be the world's largest cannabis-seed library. Rick Doblin suggests a solution to NIDA's ailing medical-marijuana program. And Lester Grinspoon argues that cannabis should not be "pharmaceuticalized." Learn more about the Aboveground Marijuana Economy -- all on fastcompany.com

One night in late September, Ethan Russo stood before a classroom packed with students on the University of Massachusetts' Amherst campus, and asked how many of them had been through the popular secondary-school program known as Drug Abuse Resistance Education, or DARE. Almost every hand in the audience went up. "Just as I thought," said Russo. "Well, we're going to hit that one head-on." He then cheerfully presented his version of what can only be described as a drug reeducation program.

Russo is a physician specializing in child neurology and one of the world's pioneering investigators into the therapeutic uses of pot. A slight, preternaturally good-humored man, Russo exhibited an outsized knowledge of his subject. Sticking strictly to the botanical name, Cannabis sativa, he noted that the plant's effects on the mind and body were first recorded by the ancient Assyrians in 2200 BC. These days, cannabis is used, mostly illegally, to relieve the nausea that accompanies chemotherapy, stimulate the appetites of AIDS sufferers, prevent blindness induced by glaucoma, suppress migraine headaches, and reduce the pain and muscle rigidity that accompanies multiple sclerosis.

Although nonprescription medications such as aspirin kill thousands of people every year, not a single death has ever been attributed to a cannabis overdose. The "therapeutic ratio" of marijuana is estimated to fall somewhere between 20,000 and 40,000--meaning it would take that many times a normal dose to kill you. If the drug is delivered as a pill or a spray (smoking just about anything is bad for you, after all), then Russo is unequivocal: "Cannabis is a safer medicine than almost all of the standard pharmaceuticals available today."

As he spoke, Russo clicked through a dazzling slide show: verdant fields of cannabis covering the foothills of Morocco's Rif Mountains; Thailand's marijuana plants on steroids, taller than a NBA center. But the most compelling slide was of a homely, quart-sized bottle labeled "Cannabis Tincture," which seemed to symbolize this country's inconsistent attitude toward medical marijuana. The United States has at times embraced the cannabis plant and its products: From the mid-19th century up until the mid-20th century, cannabis was a mainstream medicine, listed in the U.S. pharmacopoeia. The company that marketed the bottle of tincture was none other than Eli Lilly, the $11 billion behemoth that today is best known for another mood-altering drug, Prozac.

More recently, of course, the U.S. government has cast cannabis as a pariah drug. This past June, Karen Tandy, the first woman to head the Drug Enforcement Administration, declared that marijuana "has not been shown to have medical benefits."