POPS, meaning indoor or outdoor spaces that private real estate developers have promised to provide and maintain as public amenities in return for the right to build bigger buildings.

Exactly. We’ll get to a few of them on 42nd Street. Let’s head east to Bryant Park, a privately run city-owned public park, which I think it’s fair to say, back in the ’70s and ’80s, most people were scared to death to go into because it was a drug haven and dangerous.

Made worse by design features like being raised on a plinth and screened by hedges.

In the early ’80s, Andrew Heiskell, chair of the New York Public Library, next door, with support from the Rockefeller Brothers Fund and others, created the Bryant Park Restoration Corporation — now just the Bryant Park Corporation — as a not-for-profit organization under the leadership of Dan Biederman, and they brought in William Hollingsworth Whyte.

Holly Whyte, the sociologist and urbanist. He suggested getting rid of the obstructing hedges, widening the stairs from Sixth Avenue, installing movable chairs, a Christmas market and skating rink in winter. Andrew Manshel, who worked on the park and has written a book about it, calls it “a triumph of small ideas.”

Jane Jacobs gets all the play, but Holly Whyte deserves to be celebrated more than he has been. All this happened in the late ’80s and ’90s, around the same time as the appearance of a legally created vehicle called the Business Improvement District, or BID, which Biederman had pioneered up the street at Grand Central Terminal. The Bryant Park Corporation took on some of the characteristics of a BID, meaning a private, not-for-profit that managed the park.