BBC's political editor Andrew Marr on what Greg Dyke's resignation means for the corporation and for future relations with the government.
A lot of people in the BBC will be very saddened by this because Greg Dyke was an inspirational leader to many within the organisation.
Greg Dyke has resigned from BBC
There will be many around the BBC who will be very concerned with the editorial independence of the BBC and there is a big problem for the government now. The first thing they have to do is to start the procedure to appoint a new chairman.
We have an acting chairman of the board of governors and an acting director general and who knows who else will be acting for the BBC if there are to be more resignations to follow.
This leaves the BBC feeling a bit leaderless, a bit rudderless at an extremely dangerous political moment for the BBC.
I don't know what kind of character the government are going to be able to find as the new chairman. Somebody who commands the respect of BBC staff and journalists and is also seen to be strong enough to be an independent figure and acceptable to the government.
There will be jubilation in government at this announcement of course. They got everything they could possibly want.
I think you could detect from Greg Dyke and Gavyn Davies's comments that there are those in the BBC who feel that Lord Hutton didn't give a full and fair account of the wider issues and they will want to return to those issues in the future.
This business of charter renewal, which sounds a bit abstract, is actually very important.
It's about who pays for the BBC, how much the licence fee should be, how big the BBC should be, should it be able to sell magazines, should it have an online presence?
And should the governors, who have been the ruling body of the BBC right back to the 1920s, have their powers taken away from them?
All of those are enormously political questions which now lie in the hands of this government.
Ministers insist to me that they are not going to be allow what happened in the Hutton process to infect their judgement, they are going to be fair.
Meanwhile, it is up to BBC journalists to make sure they are not going to be cowed or frightened by the extraordinary events of the last 48 hours.