It was written by Bunton and Jamie Hartman for her third studio album, Life in Mono (2006), while production was helmed by Simon Franglen.

John Murphy from MusicOMH called the song "similarly arresting," describing it as "a beautifully tender piano ballad that the likes of Lucie Silvas would be well advised to take note of,"[1] while Liz Hoggard, writing for The Observer, deemed it "breathtakingly lovely.

"[2] Fraser McAlpine of BBC Radio 1's TheChartBlog wrote: "The first verse is wafty and piano-led, then there's a quiet chorus, then the drums kick in for a meatier version of same", while adding "the dragging pace and out-dated 'classy' production are going to get really boring, really quickly" and comparing it negatively to the Spice Girls's 1998 song "Viva Forever.

"[3] First announced as the album's second and final single on Bunton's official site,[4] "All I Need to Know" was made available by Universal Music as a download from 5 February 2007.

[8] The visuals were originally inspired by the photography of fashion photographer Peter Lindbergh,[9] and feature Bunton as an angel watching over various lonely people, none of whom can see her.