Architectural Digest: Tell us about your inspiration for the new David Zwirner gallery in Manhattan. High-quality raw concrete like what you used on the façade and interior stairwell is such a rarity in New York City—I think builders and clients generally try to avoid it. How did you get away with it?

Annabelle Selldorf: It wasn’t at all about “getting away with it.” David, who has been a client for 20 or so years, said, “Look, I bought this building, we’re going to tear it down and make gallery space, and I know exactly what kind of galleries I need.” So coming up with the program was pretty easy. And then we asked ourselves, Well, what does this building look like? All clients think that they are architects. David in particular is a very, very good client. He’s articulate and has particular expectations for a space. Truthfully, it was David who wanted the building to be cast-in-place concrete. But like any layperson, he didn’t necessarily know what that entailed. He just knew that he wanted a certain look and feel. And I, knowing more about what it takes to actually do a concrete structure, realized this posed a formidable challenge.