Marina Lambrini Diamandis ( DEE-ə-MAN-diss; Greek: Μαρίνα-Λαμπρινή Διαμάντη, romanized: Marína-Lampriní Diamánti; born 10 October 1985), known mononymously as Marina (often stylised in all caps) and previously by the stage name Marina and the Diamonds, is a Welsh singer, songwriter and record producer.

Born in Brynmawr and raised near Abergavenny, Diamandis later moved to London to become a professional singer, despite having little formal musical experience. In 2009, she came to prominence upon placing second in the BBC's Sound of 2010. Her debut studio album, The Family Jewels (2010), incorporated indie pop and new wave musical styles. It entered the UK Albums Chart at number five and was certified gold by the British Phonographic Industry. The album's second single, "Hollywood", peaked at number 12 on the UK Singles Chart. Diamandis' second studio album, Electra Heart (2012), was a concept album about a character of the same name. The album explored electropop and dance-pop and became her first number one album in the United Kingdom. It was certified gold in the US and UK, and respectively produced the successful singles "Primadonna" and "How to Be a Heartbreaker".

Diamandis' Europop-inspired third studio album, Froot (2015), became her third top 10 album in the UK and her first top 10 entry on the US Billboard 200. In 2018, she was featured on Clean Bandit's single "Baby", which reached the top 15 in the UK. Her fourth studio album, Love + Fear (2019), charted at number five on the UK album chart. In 2021, Diamandis released her fifth studio album, Ancient Dreams in a Modern Land, which debuted at number 17 in the UK, and was followed by a deluxe version in 2022.