The BBC's admission that at least six programmes breached editorial standards by faking phone-ins has led the corporation to announce a "zero tolerance" approach to any future errors.
The BBC's media correspondent Torin Douglas answers some key questions about the potential fallout.
How significant a crisis is this for the BBC?
This is as serious as anything as it's all about trust between the broadcaster and audience. Listeners and viewers as well as BBC staff are shocked about the six programmes where producers made up competition winners.
Are heads likely to roll at at the BBC?
It certainly sounds like people are going to be suspended - "editorial leaders" as Mark Thompson describes them, may well have to step back from their jobs as inquiries take place. In Sports Relief when a competition winner was a member of the production team, it was discovered this was a contingency plan made in advance. This is a case where someone may have to take a back seat while it is investigated.
How do you think morale at the BBC will be affected?
Mark Thompson's action plan will be a 'wake-up call'
Very badly. Those people who have tried to tell the truth and not misled people over the years will be shocked to hear this has been going on. But the worry is how many people are there in the BBC who haven't realised this is the sort of thing you're not meant to do?
How will the BBC restore faith with its audience?
By announcing this series of measures so publicly, Mark Thompson has probably done more than other broadcasters would be expected to do. It shows that the BBC is taking this very seriously.
What will the shockwaves be for the broadcasting industry as a whole?
Ofcom gave a very damning report about the state of phone-in competitions, and it's those sort of programmes who have been implicated in the BBC probe.
The BBC thought it had a strong culture in terms of trust, but this shows that with new people coming into the industry including independent producers who have never worked for the BBC, maybe the culture was not as strong as we thought it was.
What are other broadcasters planning to do in response to the BBC's measures?
Various broadcasters have already responded by admitting their own transgressions. ITV chairman Michael Grade had said the industry as a whole needed to take this seriously.
We have heard for several weeks that this was a wake-up call - if they haven't woken up before, they're certainly going to now.