When playwright Lynn Nottage and director Kate Whoriskey begin researching a play together, the process resembles journalism more than theatre-making. That was true of their collaboration on Nottage’s Pulitzer winner Ruined—for which they traveled to the Democratic Republic of Congo—and remains true today, 16 years after their first collaboration, Intimate Apparel.

On their trip to Central Africa, they each kept lists of what intrigued them during the day and would share them at night.

“My lists tended to be about encounters that we’d had, and things that we’d heard,” says Nottage. “Kate’s lists tended to be about things that she’d seen—movements and gestures. When we put our lists together, there was a complete experience. That’s what happens when we work on a play—it’s a combined vision.”

In 2011, they were ready to begin the process again. Nottage took a trip to Reading, Pennsylvania, in search of a narrative and, a few months later, Whoriskey joined her in interviewing as many people as possible—in homeless shelters, in local government, and in factories. They were looking for a story that would reflect what was happening to American culture. Inspired by what they found, Nottage wrote Sweat.

Sweat tells the story of a group of friends who have spent their lives working together on the factory floor. When rumors of layoffs begin to stir, rifts form that chip away at their trust and pit them against each other. A play about friendship, loyalty, race, love, and the economy, Sweat played to critical acclaim at the Oregon Shakespeare Festival and Off-Broadway at the Public Theater and will mark Nottage’s Broadway debut when it begins previews at Studio 54 March 4.

In Reading, Nottage asked Whoriskey to simply “go out and ask questions.” Those were her only instructions. The two share an openness and curiosity—part of what makes their collaboration so successful.

“What is exciting about her approach is that there is truly a blank canvas,” says Whoriskey. “That’s a place of fear. You hope something, a story, will come back.”

“We’re drawn together because we share a worldview,” agrees Nottage.

“There’s a commitment to a friendship [as well as working relationship],” says Whoriskey. The success of Sweat is a shared milestone for both. “We’re in a moment of celebration,” says the director, prompting a smile from both.

Sweat begins previews March 4 with an official opening March 26 at Studio 54.