"Green Light" is a song by New Zealand singer and songwriter Lorde. It was released on 2 March 2017 through Universal Music New Zealand as the lead single from her upcoming sophomore album, Melodrama (2017). Lorde co-wrote and co-produced the song with Jack Antonoff, with additional writing from Joel Little and production assistance from Frank Dukes.

Prior to the song's release, Lorde teased the song on her Twitter account, saying the "Green Light" would be "different, and kinda unexpected. Complex and funny and sad and joyous and it'll make you DANCE." Lorde announced the release of the single and its music video on Twitter on 2 March 2017. Later that day, in a Beats 1 interview with Zane Lowe, she also said:

The song is really about those moments kind of immediately after your life changes and about all the silly little things that you gravitate towards. I say, 'She thinks you love the beach, you're such a liar.' What the fuck, she thinks you like the beach?! You don't like the beach! It's those little stupid things. It sounds so happy and then the lyrics are so intense obviously. And I realized I was like, 'how come this thing is coming out so joyous sounding?' And I realized this is that drunk girl at the party dancing around crying about her ex-boyfriend who everyone thinks is a mess. That's her tonight and tomorrow she starts to rebuild. And that's the song for me.

In an interview with MTV, she revealed "Green Light"'s piano part was inspired by Florence and the Machine's "big, jangly" piano movements.

The song was written by Lorde, Jack Antonoff, and Joel Little, with production being handled by Lorde, Antonoff, and Frank Dukes. It was the first track Lorde wrote for Melodrama. Writing took place over an 18-month period. Lyrically, the song is inspired by Lorde's first heartbreak, with reviewers characterizing the lyrics as being "downbeat" as well as having an "acceptance of longing".

Musically, "Green Light" is described as an electropop, dance-pop, and indie pop song. According to sheet music published at Musicnotes.com by Sony/ATV Music Publishing, "Green Light" is set in common time with a "driving" tempo of 129 beats per minute. The song is composed in the key of A major, with Lorde's vocal range between the notes D₃ and A₄. "Green Light" begins with Lorde singing solo with a lone piano playing "slow, steady" power chords consisting of a root note and the fifth above. Then, in the first of the song's two pre-choruses, a "throbbing beat" plays amid "tongue-twisting lyrics, eerie background vocals, and bubbling electronic effects." In the second pre-chorus, a "cheery, upbeat piano loop and a kick drum" accompany Lorde as she sings about an "uneasy new reality". The chorus that follows this section has been described by BBC as "euphoric" and by Forbes as power pop, with the addition of hand-claps, bass and strings. Here, the titular metaphor comes in the form of a hook: "I’m waiting for it, that green light—I want it," with reviewers interpreting the "green light" as a street signal that gives the singer permission to move on into the future.

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Wikipedia