COFFEE solves crimes.

Or at least it helps to. Over the last few weeks Scotland's new anti-gangster HQ, the Crime Campus at Gartcosh, has gradually become fully operational. Everything, that is, except a much-awaited espresso bar.

But its workers - police and prosecutors, tax investigators and forensic scientists - are still getting their caffeine fixes, little cardboard cups of stewed black liquid from Thermoses in their first-floor canteen.

And as they do so, they talk to each other; they talk to each other about how to beat organised crime; how to catch international fugitives or tax cheats on the run.

"I keep bumping into people I would have waited months to see in the past," explains David Odd, HM Revenue and Customs' assistant director of criminal investigations in Scotland. "It's incredible."

Weeks in to the Crime Campus it is still too soon to say how big the caffeine effect will be. But, as Mr Odd speaks, around him in the huge, naturally lit atrium, little huddles of crimefighters are forming over coffee and papers stamped with red "protective markings".

One is Detective Chief Superintendent John Cuddihy, head of organised crime and counter-terrorism at Police Scotland. "There are no doors," he says, waving across the open-planned stairway. "You can walk from one end to the other. You can't help talk. There there is no excuse for not sharing information.

"There is an infectious enthusiasm and there is a collective drive. When you walk in here in the morning, you feel it. You are talking to people from a whole lot of different organisations but you don't distinguish between them. Everybody has got the same badge, individuals who work for the crime campus and have the objectives of the crime campus. Of course, they will work for organisations with their own objectives. But while they are here operating in Scotland their objective is to keep Scotland safe. That is it."

All the main bodies in the Crime Campus - Police Scotland, the national forensic service, the UK National Crime Agency, HMRC and the Crown Office - make the same point: their 1200 staff are gelling into one team.

That was why the Scottish Government decided to build the £75 million four-storey HQ.

Yet it didn't have to be this way; it wasn't obvious that the campus, first planned by the old Scottish Crime and Drug Enforcement Agency (SCDEA) and the previous Labour-Liberal administration, would happen. Why? Because although the aims of the main partners may overlap, they are not exactly the same.

Nor are their paymasters. Some, such as HMRC and the NCA, are funded by the UK government, others by the Scottish, which paid for the building and collects the rents.

Take prosecutors. There is an inevitable and - many legal minds would argue - proper tension between the Crown Office and Police Scotland. Prosecutors, after all, hold law enforcement to account on the quality of its evidence. Lindsey Miller, who heads the Crown's serious and organised crime division, and is now based at the Crime Campus acknowledges this. "We are in a slightly different mode.

"You have us and then you have law enforcement, such as the police or the HMRC or the NCA. I have heard comments from some legal establishment friends who have asked 'Is it not a bit dangerous to have prosecutors embedded with police?'.

"But I think it is the way forward, particularly in the cases we deal with. This isn't a change of culture for us in the way it might be for other organisations.

"Now we are all under one roof and we can access all sources of knowledge and experience and be able to shape and direct investigations at an early stage. There is a perception Crown gets cases at the very last minute. But for the cases we deal with we are involved right at the beginning, possibly from intelligence development stage.

"My team is able to advise whether the techniques law enforcement are deploying will work for our prosecution. "

A simple example of how the Crime Campus helps inter-agency work: there are legal documents that can only be delivered in hard copy. Miller said: "We are restricted on what you can send by email. You used to have to meet somebody in shady place and hand over a brown envelope. Being here cuts that all out."

Scotland's main forensic science base is now also at Gartcosh. But forensics are not part of the police force, they answer directly to the police authority. The scientists, like the Crown, are not the police. Yet their presence at the campus has opened new possibilities to discuss how their science can help tackle crime - and not just comparing footprints or DNA.

Tom Nelson, the service's head, admits it's "early days" but is already wondering out loud how his colleagues might help HMRC. The Revenue, in turn, has different but overlapping priorities to the police: their main job is raising money. But they also have unique intelligence vital to the police.

The NCA, meanwhile, is the gateway to Europol and those across the UK tackling gangsters who rarely respect national borders.

Ruaraidh Nicolson, the assistant chief constable of Police Scotland, stresses all the agencies are just "liaising". "We are working together. It doesn't matter who leads on an investigation, it will be whoever is the most appropriate." Sometimes that will mean HMRC tackling an organised criminal; sometimes NCA, sometimes another partner, he said.

Gartcosh already has representatives from trading standards and the civil nuclear and the MOD police forces. Others are welcome, such as the Scottish Environment Protection Agency, increasingly important as the Scottish underworld moves into illegal landfill operations, or the Security Industry Authority. By the time they come, the espresso bar will be open.