Stephen Sondheim & David Ives

But not content merely to revisit the past, Sondheim speaks of pushing forward and says he has "20 or 30 minutes" written of a new musical that he is collaborating on with American playwright David Ives, a New York regular little known in London. "Having spent the better part of four years writing two books [both sizeable tomes in which he anatomises his own career as lyricist alongside that of others], I'm really rusty. I sit at the piano and think, 'Where's middle C?' Any muscles, as you know, atrophy when you don't use them, and I haven't been using my musical muscles."

http://www.thisislondon.co.uk/theatre/article-24039487-in-new-york-were-starved-of-plays.do