More than simply a supergroup, Trio was a reinvention and a reunion—a record that erased genre boundaries and quashed assumptions as it created a new template for women country artists to collaborate with one another. It is country music at its most traditional, but performed by some of the most recognisable voices in 20th century popular music: Dolly Parton, by then a titan of Music Row (if still an often belittled one); Linda Ronstadt, on the tail end of her titanic ’70s run as a country-pop-rock megastar; and Emmylou Harris, an outlaw and iconoclast who made a country career doing exactly as she pleased. It took more than a decade after the women first sang together to actually make the record—understandable, given the obligations of their individual careers and record deals. But they all stayed the course, addicted to the sound that they made together. “When we heard our voices, it was like injecting some kind of serum into your veins—it was a high like you’ve never felt,” Parton said later. Ronstadt and Harris had bonded early on over their love of Parton, and though all three were roughly the same age, they revered her. “Sometimes we would disagree about who would sing lead, because Emmy and I would always want Dolly to sing lead on everything,” Ronstadt said. Parton doesn’t always take lead, though; instead, the singers take turns out front of the lush harmonies, which in turn rest atop the sweet acoustic sounds of the all-star backing band. The Teddy Bears’ “To Know Him Is To Love Him” gets an entirely new life (with lead guitar by Ry Cooder) via Harris’ rangy warble, while the trio channels Appalachia on “Those Memories of You” and Parton’s composition “Wildflowers”—a modern classic—and early hillbilly music on Jimmie Rodgers’ “Hobo’s Meditation”. Their powers combine for a flawless effort, a canonical album by three superlative artists who have always refused to fall in line—this time, performing hand in hand.