Raymond Edward "Gilbert" O'Sullivan (born 1 December 1946) is an Irish singer-songwriter who achieved his most significant success during the early 1970s with hits such as "Alone Again (Naturally)", "Clair" and "Get Down". His songs are often marked by his distinctive, percussive piano playing style and observational lyrics using word play.

Born in Waterford, Ireland, O'Sullivan settled in Swindon, England, as a child. In 1967, he began pursuing a career in music. Worldwide, he has charted 16 top 40 records including six No. 1 songs, the first of which was 1970's "Nothing Rhymed". Across his career, he has recorded 19 studio albums. The music magazine Record Mirror voted O'Sullivan the top UK male singer of 1972. He has received three Ivor Novello Awards, including "Songwriter of the Year" in 1973.