Marina Lambrini Diamandis (born 10 October 1985), also known by stage name Marina and the Diamonds (sometimes stylised as Marina & the Diamonds), is a Welsh singer-songwriter. She rose to fame after reaching number two on the BBC Sound of 2010 poll list, coming second to Ellie Goulding. After releasing one private EP, Diamandis released her second extended play, The Crown Jewels EP, with help from Neon Gold Records, in 2009. Now signed to 679 Recordings, she released her debut full length studio album, The Family Jewels, followed by her third extended play, The American Jewels EP, in 2010. In 2011, Diamandis announced that she was working on her second album, Electra Heart, which was released in April 2012 and went to #1 in the UK and Ireland.

Her stage name, "Marina and the Diamonds", consists of Diamandis' first name and the translation of her surname, which means "Diamonds" in Greek. According to her, "The Diamonds" are not her backing band, but her fans.

Diamandis' musical style ranges from keyboard-based ballads to more up-tempo New Wave-style songs with full band backing She has cited a wide-range of influences such as Daniel Johnston, Blondie, The Distillers, Patti Smith, Tom Waits, Garbage, Nirvana, PJ Harvey, Kate Bush, Britney Spears, Yann Tiersen, Elliott Smith, Dolly Parton, and Madonna.