What’s the secret to a successful dinner party? The seating arrangements, of course.

Some thought and care—an eye toward which of your friends will have the most in common, who will help bring others out of their shell, and who, for everyone’s sake, should be seated at opposite ends of the table—goes a long way. Now, imagine you’re planning a dinner for hundreds of celebrities, designers, industry leaders, and more special guests, all at The Metropolitan Museum of Art, for the annual fundraiser for the Costume Institute. How, exactly, does Vogue do the seating chart for the Met Gala?

It all begins with a seating document as early as December, five months before the event, when the guest list begins to take shape.“The actual chart does not really come together until about a month before the event, once we have a clearer sense of the room, the layout, and the flow of the evening,” says Sache Taylor, Vogue’s director of special events.

Taylor, along with Eaddy Kiernan Bunzel and the rest of the events team, spends practically all of April in a conference room at the Vogue office, going over the seating chart, which lives on a large poster board that is kept top secret. Guest names are listed on Velcro tabs known as “Lilah labels,” named after their inventor, Vogue’s own Lilah Ramzi. The Velcro is key, because the chart is a “constantly moving puzzle,” Taylor says.

“We are still making adjustments right up until the very end. It’s not just the guests that are changing, but the floor plan as well, so we are continuously refining as things shift. It’s part strategy, part instinct, and occasionally a bit of musical chairs,” she shares.

The goal is for guests to have fun and connect with each other. “We spend a great deal of time thinking about who is sitting next to whom—ideally pairing people who will have an immediate connection, or perhaps discover they have more in common than they realized,” Taylor says. The Vogue team considers sight lines, table placement, and the overall composition of the room, “making sure everyone has a good view of the stage, and, whenever possible, not of a former flame,” Taylor adds.

Kiernan Bunzel, who has worked on the Met Gala for more than a decade, keeps an archive of every seating chart she’s worked on. The result is a cultural archive that maps creative collaborations, romances, and friendships that may have come out of the seating pairs at the gala. “They’re almost little time capsules of what was going on each year,” she says.