Lorde has been named Best International Female Solo Artist at the Brit Awards, and she called the honour a "priceless surprise".
Lorde beat Janelle Monae, Katy Perry, Lady Gaga and Pink to the award, which was given to her during the star-studded Brits ceremony at the O2 in London.
The 17-year-old told the crowd: "I'm still so new to getting awards that my brain feels like it's exploding every time it happens, so forgive me.
"Thank you to the strong, intelligent, inspiring women in this category. This really was a priceless surprise."
Lorde may have been subtly mocking the event's sponsor, MasterCard, with her final words.
Reports that a PR firm asked journalists to promote MasterCard's sponsorship of the event by tweeting about the company with the hashtag "PricelessSurprises'' in exchange for entry led to a flurry of online criticism.
Journalists and music fans lined up to mock the public relations firm, House PR, which represents MasterCard.
Ed Hayes tweeted: "Having your crass social media campaign backfire on you spectacularly #PricelessSurprises'', while David McGuire wrote: "Monstrous PR fail #PricelessSurprises''.
Ginny Paton, MD at House PR, said: "The role of the PR agency is to pursue all coverage opportunities on behalf of its clients.
"This includes providing accurate brand references from the outset, for use across all platforms. It is a two-way conversation between the journalist and the PR in order to reach a mutually beneficial outcome. Editorial control always remains with the journalist.''
She later tweeted this about her win:
this is me being stoked winning a brit look at my cute chubby face pic.twitter.com/34QuVKJYYk
In a press conference after the awards, Lorde said the highlight was seeing two music greats: ""Everything has been cool. Beyonce is always amazing. Prince walked past me in the corridor, and that was the craziest moment ever, to share some air with Prince. No big deal."
Earlier, Lorde performed with British electro group Disclosure.
Introduced by host James Corden as "two of the biggest new acts to come through this year", the chilled-out performance was backed by a giant outline of Lorde's face made of lights. The 17-year-old was dressed in a long, black sequined dress.
Halfway through the relaxed electro reworking of Royals, the song switched to Disclosure's White Noise, with AlunaGeorge taking over the vocals.
The Brit appearance comes hot on the heels of Lorde's double Grammy win in Los Angeles last month, when she won the Best Pop Solo Performance and Song of the Year gongs for her smash-hit Royals.
But it was UK rockers Arctic Monkeys who opened the Brit Awards, with a fiery performance of RU Mine before they went on to win best band and best album gongs for the third time.
Ellie Goulding picked up the evening's first award - best British female solo artist - which was presented by special guest, Prince. Meanwhile David Bowie picked up his first Brit Award in18 years for best British male, but the 67-year-old chose to stay home in New York rather than attend the London ceremony.
Supermodel Kate Moss collected the prize on his behalf, decked out in one of the singer's Ziggy Stardust outfits.
Bowie previously won the prize 30 years ago, and the only other win he has notched up during his long career was an honorary title in 1996 for his outstanding contribution to music.
Watch Lorde's performance with Disclosure and AlunaGeorge:
Moss arrived secretly, avoiding the red carpet, to surprise guests at the event. When she arrived on stage, the 40-year-old model was wearing an outfit that Bowie had made famous at one of the most celebrated stages of his career.
Moss and Bowie have had an association for a number of years, with the model interviewing Bowie for Q magazine more than a decade ago, also posing for a cover shoot together.
With Thursday night's win he has become the oldest star to be awarded a Brit, succeeding Sir Tom Jones who was 62 when he picked up his outstanding contribution prize.
Bowie returned to the music world early last year surprising his fans by coming out of what had appeared to be retirement, releasing his album The Next Day after a 10-year recording silence.
Other winners included Bastille, Bruno Mars and One Direction.
WINNERS OF THE 2014 BRIT AWARDS:
British Female Solo Artist - Ellie Goulding
International Male Solo Artist - Bruno Mars
British Breakthrough Act - Bastille
British Group - Arctic Monkeys
Best Producer - Flood & Alan Moulder
British Male Solo Artist - David Bowie
British Single - Rudimental, Waiting All Night
British Video - One Direction, Best Song Ever
Critics' Choice Award - Sam Smith
International Female Solo Artist - Lorde
International Group - Daft Punk
MasterCard British Album of the Year - Arctic Monkeys, AM
- nzherald.co.nz with AAP and AP