"Quién" is a song written by Guatemalan singer-songwriter Ricardo Arjona for his third compilation album, Quién Dijo Ayer (2007). The song was released on June 19, 2007, as the lead single from the compilation.

"Quién" is a latin pop song written by Ricardo Arjona. The music was composed by Tommy Torres, who also worked with Arjona on Adentro. The song was produced by Lee Levin, Dan Warner and Torres with additional help from Arjona. "Quién" is performed by Arjona with additional background vocals from Tommy Torres.

The song was recorded between five studios in Miami: The Tiki Room, Picks & Hammers, Jet Wash Studio, The Hit Factory Criteria and Hit Masters; and on Jocoteco Studios in Mexico City. "Quién" was mixed in Barking Doctor Studios in New York City by Mick Guzauski, and mastered by Vlado Meller at the Sony Music Studios on that city.

Arjona commented that "'Quién' is the world out of the window and the prison built by ourselves. It's the freedom to chose the path or to prefer loneliness as an argument of nostalgia. 'Quién' is a story with the hurry of the desperate, is the flashback of those who end up loving alone."