H.B.A. turns hoodies and multipocketed jackets into avant-garde objects. Photograph by Jeremy Liebman for The New Yorker

One afternoon in 1999, when the designer Shayne Oliver was in the sixth grade, he came across a magazine ad for Dirty Denim, a line of “pre-soiled” jeans by Diesel. The ad featured a collage of faux paparazzi photographs documenting the meltdown of a fictional rock star. Oliver was struck by the campaign’s tagline: “The Luxury of Dirt.” “That blew my mind,” he told me recently. “Spending money on something that looks dirty? I was, like, ‘This is genius.’ ” He informed his mother, a schoolteacher from Trinidad named Anne-Marie, that he needed a pair immediately.

Oliver’s father had abandoned Anne-Marie before Shayne was born, and she had struggled to raise him on her own. They lived in a tiny apartment on Halsey Street, in Bedford-Stuyvesant. Oliver, who attended some rough schools—he witnessed knife fights in the halls—was highly intelligent, and Anne-Marie was determined to nurture his gifts. She stood up to people on the street who heckled him because he was effeminate, and fought with school officials who wrote him off as a rowdy black kid. She didn’t have the money for the jeans, which cost three hundred and seventy-five dollars, but she respected Shayne’s sense of urgency. “How are we going to afford Diesel clothes?” she asked herself. She soon began working evenings at the Diesel store at the corner of Sixtieth and Lexington. She got an employee discount, and her kid got his jeans.

Oliver began accompanying Anne-Marie on her shifts at Diesel, folding shirts, examining seams, and offering customers unsolicited style advice. Although his suggestions were impeccable, after a few weeks the management told him to stay home, noting that it was illegal for twelve-year-olds to work in retail. Undaunted, Oliver walked a few blocks to a Roberto Cavalli store. Employees there were so charmed that they offered him an unpaid internship. He didn’t take it, but he continued to visit the store—and pester the staff. “I would just be in the shop, hanging out all the time and talking shit,” he recalls. “It was fun.”

Oliver was a recent arrival in New York. He was born in 1987 in Minnesota, where Anne-Marie had immigrated to pursue a teaching degree, and he had spent his childhood shuttling among female relatives in St. Paul, St. Croix, and Trinidad, before settling with his mother in Brooklyn, in 1998. In St. Croix, at the age of five, he had begun making his own fashions out of scraps of fabric scavenged from his grandmother, a dressmaker. After moving to the United States, he started cutting up items in Anne-Marie’s wardrobe. In an effort to discourage this practice, she took him on regular trips to Jo-Ann Fabrics. He kept looting her closet.

When Anne-Marie rode the subway with Oliver, she noticed him staring at men who were wearing streetwear brands like Mecca and FUBU. “Why are you looking at all of these guys?” Anne-Marie asked him. “You’re all up in their Kool-Aid!” Oliver protested that he was inspecting them for their clothes, which was only half a lie. He began cutting up his jeans and ripping out the crotch, which made him a target at the Pentecostal church that he and his mother attended. “I was being expressive!” he recalls, adding that other parishioners expressed themselves by speaking in tongues. At thirteen, he quit the church.

That year, Anne-Marie sent Oliver to a public school in Long Island City which focusses on the arts. For weeks, he came to class wearing a head scarf, and was often mistaken for a Muslim girl. (“I should’ve played that up a little bit,” Oliver told me. “Muslim girls get a lot of attention.”) Shortly after he enrolled, Anne-Marie rented for him a videocassette of “Paris Is Burning,” the 1990 documentary about voguing competitions in New York. A year later, he became a member of the House of Ninja, one of the groups featured in the film. “The Ninja people were all offbeat and not glamour kids,” he recalls. They encouraged him to explore various looks, and in competitions, he said, he “swayed between ‘vogue femme’ and ‘runway.’ ”

As a teen-ager, Oliver began applying his ingenuity to his hair: “There was one point where I was mixing textures—it was, like, a mullet of dreads and then permed on the sides. I’m sorry, that hairstyle was so nasty! It was ridiculous. It was so good.” He went out most nights, commuting between the largely white electroclash scene centered on Club Luxx, in Williamsburg, and the mostly black and Latino scene on Christopher Street, where he liked to “smoke, go to the pier, and then vogue.”

Before entering the tenth grade, he transferred to Harvey Milk, the country’s first high school for L.G.B.T. youths. Many of the students there wore three outfits a day: one for their neighborhood, one for school, and one for going out. It could be dangerous to wear the wrong thing in the wrong place, so kids kept outré clothes in their backpacks and changed on the subway platform. Oliver, though, prided himself on assembling outfits that worked in all three environments: butch enough for Bed-Stuy, smart enough for school, glam enough for the club. He devised subtle, colorless ensembles, the drape and shape of which sent coded messages to the educated eye. “If you have on all-black, you can go unnoticed on the block,” Oliver explained. “Then you go into the city, and someone who’s thinking about clothing in a different way notices all the cuts and layering.” Styling choices helped him adapt his look to different contexts. Oliver liked wearing tight poom-poom shorts, but on his way to school he pulled them low, so that they sagged “in a masculine way.”

At Harvey Milk, Oliver made friends with another boy who was obsessed with fashion, James Garland. Each was an only child, raised by an indulgent single mother who had given her son the master bedroom. They recorded television broadcasts of runway shows and pored over the designs. Garland liked the debonair luxury of Tom Ford; Oliver preferred the forbidding moodiness of Rick Owens. Before long, the boys began making clothes, conducting photo shoots in Fort Greene Park, and staging runway shows at school. They generated new pieces through collage, stitching together items from vintage shops, children’s jackets from thrift stores, and treasures from their mothers’ closets.

After creating their first line of T-shirts, named Ammo, and their first collection, Cazzy Calore, Garland and Oliver graduated from Harvey Milk and enrolled at the Fashion Institute of Technology. Garland flourished there, but Oliver chafed against the curricular constraints and dropped out in his freshman year. In 2006, he diverted the tuition money that Anne-Marie had saved for him, and launched a fashion line with his friend Raul López, who also hung out on Christopher Street. Oliver called the new line Hood By Air. The phrase suggested a style that was proudly ghetto and proudly élite (“putting on airs”). Within a few years, the label had become the most prominent high-fashion brand to have emerged authentically from street culture.

Oliver’s original mission with the label was to bring to fine menswear what he calls the “thug silhouette”: the shape created by a long T-shirt paired with saggy pants, as if the wearer had a very long torso and very short legs. He also believed that he could turn streetwear basics such as oversized hoodies and multipocketed jackets into high-concept luxury items.