Lurking behind the big decisions that get made in this country are the hidden persuaders. The people who plot the words, actions and body language of our CEOs, politicians, chairman and other public figures. The people who — by providing and denying journalists information — help shape the news we read, see and hear. The people who wield extraordinary power by proxy despite often having no official claim to authority.

They spruik, they schmooze, they strategise. And although they’ve got a dodgy reputation — thanks largely to pop culture portrayals such as Thank You For Smoking and The Thick of It — they aren’t going anywhere.

As former finance minister Lindsay Tanner argues in his book Sideshow: “Spin is intensifying. Its significance is growing … People are complaining about something that they once ignored or took for granted because it now dominates our public culture.”

Media units in government departments, police forces and businesses have expanded dramatically in recent years. Corporate affairs managers in large companies — once little more than mouthpieces — increasingly report directly to the CEO and play an important role in company strategy. Public relations practitioners now outnumber journalists by around 3:1.

An analysis of Australian newspaper content by the Australian Centre for Independent Journalism in late 2009 found nearly 55% of published stories were driven by some form of public relations. And that’s wasn’t counting off-the-record briefings, arguably the most potent form of spin because of its invisibility.

“I started as a young reporter in ’73, and nobody had a full-time PR team,” Chris Mitchell, editor of The Australianexplained in 2010. “When I was a young business journalist, corporates were happy to get their chief executives to talk to reporters directly. There’s hardly a business story that’s written these days in which a chief executive has backgrounded a reporter, it’s all been done by spin doctors.”

“Spin” may be a relatively new term, but it’s not a new phenomenon. Humans have always tried to massage information to suit particular agendas. Nevertheless, spin is becoming increasingly sophisticated — and it’s something to be worried about.

At its worst, spin distorts the truth, undermines democracy and debases our language. Front groups for vested interests are promoted as genuine grassroots organisations. Results from scientific studies, opinion polls and economic modelling are distorted. Politicians avoid scrutiny by burying unfavourable announcements on the day big news events occur (as the Blair government did on September 11). Slogans and sound bites — remember “moving forward”? — replace nuanced debate. Civilian deaths in war become “collateral damage”.

That doesn’t mean all who dabble in the so-called “dark arts” should be demonised. “At the bad end spin is lying to punters,” says marketing veteran Toby Ralph. “At the good end it’s about communicating the truth well.”

While journalists love to bewail the growth of the PR industry, spinners play an important role in bringing newsworthy stories to light, answering reporters’ questions and defending those whose reputation has come under attack.

“If there was no market demand for this work it wouldn’t exist,” says veteran crisis management consultant Anthony McClellan. “We exist because the media is ferocious, often unfair and sometimes unethical. Our job is to stand between the client and the 50 journos at the gate — metaphorically speaking but sometimes not.”

Managing the media is an important part of the job for those in the PR game. But it’s not the be all and end all.

The crème de la crème of the trade — and the people we’ve rated most highly in compiling our list — are those who do more than just spin lines. These are the trusted advisers who have a say in long-term strategy, not just managing the daily news cycle. Who can influence how decisions get made, not just how they get communicated. In the jargon beloved by many a PR flack: they become inputs, as well as outputs.

“It’s not just about dealing with journos,” explains Wayne Burns, director of the Centre for Corporate Public Affairs. “It’s more about sitting around the CEO’s table with the board, trying to inform them what’s happening out there that can influence their company.

“The most important part is stopping bad things from happening.”

*Read the list of 20 contenders at The Power Index