Neo-soul’s emergence in the late 20th century happened slowly but deliberately. Artists like the restless belter D’Angelo and the shrewd songsmith Maxwell tested the boundaries of R&B’s future while luxuriating in the ideals—extended instrumental jams, off-the-charts vocal performances, rugged lyrics—that had made ‘70s albums by the likes of Al Green and Isaac Hayes classics. In the 21st century, a vanguard of artists dove headfirst into soul music’s next wave by honoring its past. The genre grew in wild, varied directions, with Erykah Badu imbuing her psychedelic explorations with hip-hop candor, Janelle Monáe taking the idea of “robo-funk” to high-concept heights, and Anderson .Paak saluting Stevie and Dre with his sweeping, genre-bending depictions of California life.