One very cold New York City morning just before Christmas, a group of women showed up to have their picture taken by photographer Cass Bird at a warehouse turned studio in the South Bronx neighborhood of Hunts Point, a chunky little peninsula that reaches out into the East River toward Rikers Island.

Those who made the trek were among those responsible for organizing the Women’s March on Washington, a mass mobilization of activists and protestors that will descend on the capital on January 21, the day after we inaugurate into office a man who ran the most brazenly misogynistic presidential campaign in recent history, and whose victory has emboldened a Republican-led Congress to wage an epic war on women’s rights.

Perhaps you’re planning to be there? Perhaps you’re bringing your mother, your grandmother, your daughter, your sister? You’ll be in good company. Per the event’s Facebook page at press time, 176,000 people are planning to attend, with another 250,000 still on the fence. It seems likely, said Linda Sarsour, one of four national cochairs acting as spokeswomen for the movement, that it will be “the largest mass mobilization that any new administration has seen on its first day.”

Ahead of our shoot, emails flew back and forth about just how many organizers we could expect to show for the portrait. First it was 10. Then 15. Fourteen women materialized, but several of them informed me that it might have been more like 20.

That fluidity says something about the Women’s March and how it functions; it’s an organic, grassroots effort that prides itself on being inclusive, intersectional, and nonhierarchical, on taking what Bob Bland (one of the movement’s cofounders, now serving as a national cochair) called “a horizontal approach to leadership.”

It’s also an all-hands-on-deck, eleventh-hour, race-to-the-finish-line kind of endeavor, which has required all 10, or 15, or 16, or 20 of its chief orchestrators to work around the clock since the week of the election. This is the type of national effort that the group’s communications czar, Cassady Fendlay, told me could take “six months to a year to plan.” These women had just over two months to pull it off.

“We don’t sleep much, as you can probably tell from all our faces,” Sarsour said drily, her own face framed by a fuchsia head scarf. She’s Brooklyn born and bred (with the accent to prove it), the Muslim daughter of Palestinian immigrants, and a veteran activist who heads up the march’s fundraising efforts. She juggles that with, among other things, her job as executive director of the Arab American Association of New York.