Sir Jonathan Sacks stands down this August after more than 20 years in a job that some people have described as tougher than the Archbishop of Canterbury's - but with better jokes.
The office of the Chief Rabbi of the United Hebrew Congregation of the United kingdom and the Commonwealth - to give it its full title - has always had close links to the political establishment.
First Edward V11 and now David Cameron have spoken of "My Chief Rabbi." A seat in the House of Lords seems to go with the territory these days. In September, Ephraim Mirvis will become the next Chief Rabbi, with ready access to the stars of the Cabinet and the Media. So what does the Chief Rabbi do? How much does it cost to run his office?
The full title is important. It's especially important to Reform and Liberal Jews who point out that the Chief Rabbi (of the United Hebrew Congregation of the United kingdom and the Commonwealth) doesn't represent them. In fact, he represents only about half of Jews affiliated to a synagogue. The fastest growing Jewish denomination is the ultra Orthodox - and he doesn't officially lead them either.
So what's the point of the Chief Rabbi? Historian Geoffrey Alderman thinks that, if there used to be a point to the office, there is no longer; Michael Howard thinks the point of the Chief Rabbi is to present a moderate religious voice in a world of growing religious extremism, and Vanessa Feltz thinks it's so that she has someone - other than herself - to argue with.
Producer: Rosie Dawson.