There is something about Katharine Gun that makes her seem an unlikely candidate for whistleblowing.
By Ben Davies
BBC News Online political staff at the TUC in Brighton
And yet this rather shy 30-year-old leaked details of an alleged plot to bug UN delegates before the Iraq war and was sacked from her job as a translator at GCHQ.
Despite spending months feeling scared and facing prosecution and, perhaps worst of all, finding herself thrust into the media spotlight she says she has no regrets.
Katharine Gun was sacked from her job as translator in June 2003
That's not to say she doesn't have words of caution for would-be whistleblowers
"Hopefully it's a decision that no-one would take lightly," she said when we met at a fringe meeting organised by civil rights organisation Liberty at the TUC in Brighton.
She describes being held overnight by the police and spending months feeling utterly isolated - not knowing quite how to cope.
"I felt very confused and alone as to what to do next," she told BBC News Online.
But she says that from what she can tell she was "treated far better" than government weapons expert Dr David Kelly who committed suicide after he was named as the source of a BBC story about weapons of mass destruction.
"The system obviously failed him," she said.
Gun on the other hand had Liberty and her union backing her up.
"There appears to have been nothing like that for Doctor Kelly."
In her case it was through the newspaper article that followed her leak that she was contacted by Liberty via her union at GCHQ - the government's communications centre.
"Of course I was still anonymous at that stage and I was very frightened of being thrown into the public eye. I did everything I could to remain anonymous for as long as possible. In fact I was anonymous from March almost up to November 2003."
Then she was charged under the Official Secrets Act, her name came out and she only escaped trial because the prosecution eventually decided not to offer any evidence.
So how does it feel to live under a cloud like that knowing your career has gone up in smoke?
She says it is very hard to describe.
"You are living that scenario every waking moment, you wake up thinking 'oh my god I'm still not out of this' and you go to bed worrying about it.
"So it's there 24 hrs a day and very few people go through that experience - we don't have many whistleblowers in the UK and so you really don't know who to turn to."
That and meeting another legendary whistleblower - former US defence analyst Daniel Ellsberg - inspired her to set up the Truth-Telling Coalition which will back whistle-blowers around the world.
"We're there to support each other and also if anyone else comes out of the woodwork we are there to support them."
Gun is very impressed by Ellsburg who she describes as the "person who produced the Pentagon papers which effectively turned the public mood against the Vietnam war".
She adds: "He's a fantastic guy - he's 73 and he's got tonnes of energy and he is very keen that the mistakes that were made in the Vietnam War aren't repeated because it took them years before they had disclosures of any degree ...
"Many regret even to this day that they didn't disclose earlier on because they could have saved thousands of troops and Vietnamese civilians."
The thing about Gun is that she seems someone who is quite quiet and conventional. Yet she says it didn't take her long to make her decision to go public.
"I was under an enormous amount of time pressure at that point they were talking about this UN resolution which was going to legalise the war in Iraq and it was a gut instinct that it was wrong and the only hope of saving lives was to get it out as quick as possible. It was a matter of just a couple of days."
And she insists there was nothing she could have done differently.
"It didn't stop the war, however it may have had an impact on whether there was a resolution which would have legalised the war - and that would have been a very dangerous precedent."