Esther Louise Rantzen, CBE (born 22 June 1940) is an English journalist and television presenter, who is best known for presenting the BBC television series That's Life!, and for her work with various charitable causes. She is founder of the child protection charity ChildLine and is currently in the process of creating a helpline for older people, to be called The Silver Line, designed to combat loneliness.

Esther was born in Berkhamsted, Hertfordshire, England, to Katherine Flora (née Leverson, 1911–2005) and Henry Barnato Rantzen (1902–1992). She has one younger sister, Priscilla N. Taylor (née Rantzen). She was educated at the North London Collegiate School and Somerville College, Oxford, where she read English, performed with the Oxford University Dramatic Society(OUDS), became Secretary of The Experimental Theatre Club (ETC) and joined the Oxford Theatre Group, performing in Oxford and Edinburgh.