That's the view of one, Professor Beau Kilmer, who was in Canberra this week for a conference at the National Portrait Gallery, hosted by the International Society for the Study of Drug Policy.

Professor Kilmer, who sat on a panel to discuss the options and issues around cannabis regulation, said that while many people were under the impression marijuana was legal in places like the Netherlands, in fact what was happening in the United States was "unprecedented".

Residents in Colorado and Washington voted in 2012 to not only remove prohibition, but allow for-profit companies start selling cannabis products.

Professor Kilmer, who is co-director of the RAND Drug Policy Research Centre, and co-author of a book called Marijuana Legalisation, said his organisation did not have an official position on cannabis legalisation.

It instead helps policymakers and stakeholders understand the options.

"The thing to keep in mind is, if you're a jurisdiction that is thinking about doing something other than prohibition ... you have a couple of options."

He explains that between prohibition and the for-profit model in Colorado, for example, a jurisdiction could allow home production or cannabis social clubs, which work like a collective.

Or there's imposing a government monopoly on production and supply, or limit participation in the cannabis market to non-profit organisations.

The same goes for medical marijuana. While people often think of the California model – where cannabis is easy to access – there are other models, such in New York which is more restrictive.

Uruguay, Israel and the Czech Republic are other countries experimenting with cannabis regulation in different forms.

The issues he warns policymakers and legislators about includes that if they were to go from prohibition to a Colorado type of model, it could be a lot harder to put that "genie back in the bottle" once the industry is developed and there are lobbyists and people invested.

Or if for-profits are allowed to be involved, you have to consider how they will target heavy users, and the 80/20 rule, which says 20 per cent of users account for 80 per cent of consumption.

But perhaps most of all he warns that it is early days yet, without the decades of research that inform alcohol policy, for example.

"Let's be honest, nobody knows how this is going to play out, it's very early," he said. "No one has done this before."