Guardian lead theatre critic Michael Billington was in conversation with Scotsman lead theatre critic Joyce McMillan about his book The 101 Greatest Plays, which was published last year.
Billington admitted that the title sounds conceited and arrogant, but said he wrote it as a challenge to himself. In fact, it came out of a casual conversation with his publisher over dinner in which he mentioned it as a possible idea and he got an answer back very soon after to say to go ahead and write it, much to his surprise.
The book was originally going to be 100 Great Plays, but it was his friend Antonia Fraser who told him that it has got to be the "greatest".
He admitted that it is "shamelessly subjective from start to finish" as "objectivity in criticism is an impossible ideal". He discovered by listing plays that he considered "great" that he prefers plays with a moral ambivalence. For instance, the book ends with King Charles III, a play in which it is difficult to establish where playwright Mike Bartlett stands.
He did put some limits on himself while making his list; for instance he only allowed himself seven Shakespeare plays and his selection, controversially, doesn't include King Lear. He said he was once "abused in a car park by Roy Hattersley for liking Coriolanus".
He also missed out Waiting For Godot; although he admits it is a great play that had a significant impact, he said he didn't include it as it has now become a play for actors to "do their thing".
However he would certainly revise his choices if he were writing it again. He was shocked himself to see he hadn't included Our Country's Good by Timberlake Wertenbaker, he has also missed out Angels In America by Tony Kushner and there is nothing by David Mamet, whom he greatly admires.
In answer to an audience question about male-female playwright balance, he said it was only when he looked at the list again that he realised there was such a big imbalance, but felt it would be dishonest to try to balance it afterwards.
Michael Billington's 101 Greatest Plays is published by Faber; the paperback edition is published on 1 September 2016.