Marijuana's ascent appears nothing short of unstoppable.

Roughly two decades ago, only a quarter of people responding to a national Gallup poll wanted to see marijuana legalized. But beginning in California in 1996 and spreading throughout the country, 22 additional states, as well as Washington, D.C., have legalized marijuana for medicinal use as of today.

How's this possible? On one hand, public approval of marijuana being used as medicine is higher than it's ever been. A CBS News poll from April 2015 showed that a whopping 84% of those surveyed across America would like to see marijuana legalized for medicinal purposes.

A growing number of countries are deciding to ditch prohibition. What comes next?

The global tide concerning marijuana legalization is slowly turning. Amsterdam, with its famous coffeeshops where smoking cannabis is OK, was once the international city most associated with legally smoking marijuana. But more countries are passing legislation either decriminalizing or legalizing marijuana in some form. In fact, almost half the states in the United States have legalized marijuana somehow — with more likely to follow suit. 

Privately held PharmaCielo Ltd. today announced that its Rionegro, Colombia based subsidiary, PharmaCielo Colombia Holdings S.A.S. has submitted its formal application to Minsalud, Colombia’s Ministry of Health, and the Consejo Nacional de Estupefacientes (National Drugs Council) to become a licensed marijuana grower and processor of medicinal-grade cannabis oil extracts, with plans to file an additional license application for export in the near future.

The farming of medical marijuana is loosening in Latin America just as steadily—actually, a bit more so—than here in the US. In Chile, the laws are a bit strange (possession, sale, and transport of recreational marijuana is illegal), but as of 2015, it's legal to cultivate the crop and to sell it in stores as a prescription medication.

Wherever legalization goes, money and development follow, and so last week we saw the official opening of Latin America’s largest medical marijuana farm, a totally legal operation a few hours south of Santiago that hopes to harvest about 1.65 tons of marijuana this spring.

Colombia joined the group of Latin American countries to legalize the use of cannabis (marijuana) for medical and scientific purposes, after President Juan Manuel Santos signed on December 22 a decree regulating the cultivation, processing, import and export of cannabis to those objectives.

With this measure, the Colombian government finally seeks to regulate these activities, in addition to owning and controlling seed growing areas, provided medical and scientific purposes, which was allowed for decades but had no regulation. What it has not legalized is cannabis use on public roads and marketing.

While much of the focus on legalizing marijuana is on the United State there are countries making real progress South of the border.

The Supreme Court in Mexico handed down a landmark ruling in November that declared overall prohibition unconstitutional. The case was brought by four individual citizens. The arguments were not some long list of regulatory details but instead a more fundamental question of basic human rights.

Story highlights

• New field grows marijuana legally for approved medical use
• Public approval of marijuana has shifted in Chile
• 86% of Chile's populace approves of medical use marijuana

There are thousands of green, leafy, marijuana plants as far as the eye can see at different stages of growth. But this is not a clandestine field of pot in the mountains of northern Mexico, guarded by gunmen on the payroll of a drug cartel. It's a cannabis production site that is not only legal, but also endorsed and regulated by the government.

Most legal plantations of cannabis in Latin America is neither in Uruguay nor in Mexico nor Peru, but in a rural area of southern 

Las Vegas—A new paper provides the first compendium of controlled substance classification systems around the world, revealing a broad spectrum of regulations but little consensus as to what works best.