This appears to be my year for reading David Lehman. I was given a copy of his The Daily Mirror, which I finished in January; this volume was suggested to me by Michael Wurster; and I'm also in the process of reading the latest Best American Poetry, of which he's the series editor.
This volume gives the history of the "New York School of Poets" through short biographies of the four central poets of that movement: Kenneth Koch, Frank O'Hara, John Ashbury, and James Schuyler. It also contrasts this movement with the Beats, of the same time period, and discusses the concept of avant-garde movements, in general. Later chapters introduce the second tier of the movement, and how the New York School influenced the rest of the 20th century, in American poetry.
I have never systematically studied or read the poets of this era, so this book was wonderful for giving me context for poets and poems I know individually, or not at all. It's a nice study in how movements happen, as well.
I was pleased to see that the movement validated playfulness in the work, and the technique of writing about what is happening in front of you, however mundane. Snatching inspiration from overheard conversations, or unusual signs, or odd transient events -- all techniques that I both use and teach -- were signature elements of the School.
I also see the origins of Lehman's The Daily Mirror in O'Hara's 'I do this I do that' poems, and other series ideas from this group.