This story appears in the August 2019 issue of National Geographic magazine.

The set is simple: a little fabric, a chair, maybe some flowers. Its inhabitants are more complex: an American mother who takes her children to visit their Mexican father every weekend. A recent deportee trying to rebuild his life. They pause what they’re doing, sit for a portrait, and leave with a printed copy. Behind the camera is Alexia Webster, a South African photographer who sets up street studios around the world. At Studio Transfronterizo, her project in Tijuana, Mexico, passing characters offer a glimpse of life on the world’s busiest land border.

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Every day nearly 100,000 people—commuters, students, visitors—legally cross from Tijuana to San Diego, California, at the San Ysidro border. Webster built her first studio in Tijuana near a café where new arrivals often stop for legal advice and a free lunch. She set up a half dozen more in the city: at a migrant shelter, on the beach where the border fence ends, in the Undocumented Café near the binational Friendship Park.

View Images In 2018 caravans of migrants from Central America began walking toward the U.S. border. Besy Samileth, a 17-year-old from Honduras, traveled with her father to pursue a dream of becoming a teacher.

Passersby who asked what she was doing often sat for a portrait. Lourdes Santiago González posed with her daughter, Brenda. She’d arrived decades earlier with her family to cross the border but after multiple failed attempts had stayed in Tijuana. At each set, lines of people waited: a former gang member deported from California. A celebrity impersonator performing on the nightclub circuit. Migrants from Honduras and El Salvador en route to the United States.

Nine-year-old Jaime Preciado nudged his dad onto the set. He wanted to “have a memory of us together” before his father went back to California.

More than a decade ago Webster was photographing for the United Nations in a refugee camp in Kenya when a man told her he’d watched photographers visit for 15 years but didn’t have a single picture of himself or his family. Webster thought of a studio shot of her grandparents with her mom as a child soon after they emigrated from Greece to South Africa. “It’s the most precious photograph I own,” she says. “It’s a connection to who I am.” Many of Webster’s subjects had fled war, leaving personal archives behind. One photo could help them rebuild.

In 2011, with a printer and a temporary portrait studio on a corner in Cape Town, Webster invited people to pose for a free session. She printed their picture on the spot. “Primarily it’s for them, for their kids, their grandkids, their lovers, their friends,” she says. “It’s a record of who they are.” Webster has since put up studios in other places, from the streets of Mumbai, India, to a refugee camp in South Sudan.

She gives few instructions from behind the camera. “The idea of the project is for people to rebuild their archive and reaffirm their identity,” Webster says. “I like for them to determine how they want their photo to be. How do you want to be represented?”

View Images Webster hopes her street studio series allows migrants like Guillermo Antonio Escobar, a construction worker from El Salvador, to rebuild the photo archives they may have lost during difficult times.