A Spanish Song at No. 1? All It Took Was Justin Bieber

In the music business, the so-called song of the summer is a release that gets so much airplay and streaming and so many views online during the warm-weather months that it becomes synonymous with summer fun. Think Drake’s One Dance or Carly Rae Jepsen’s Call Me Maybe. An early front-runner for this season’s title has something totally different going for it: It’s in Spanish. Despacito, a sensual fusion of pop and reggaeton, is topping the charts in 57 countries, from Brazil to Russia to the U.S. That means—for the first time in 21 years—the world’s most popular song is a Spanish-language release.

The surprise hit, recorded by a pair of middle-aged Puerto Ricans mainly known in the Spanish-speaking world, offers a template for how music labels can use their increasingly global reach to stretch a song’s popularity beyond its core audience. Sprinkle in a familiar voice—in this case, Justin Bieber’s—and a local-language hit can become an international pop sensation.