"The Importance of Being Idle" is a song by English rock band Oasis. It was released on 22 August 2005 in the UK as the second single from their sixth studio album, Don't Believe the Truth (2005), written, produced, and sung by lead guitarist Noel Gallagher. The song was written by Gallagher in the mid-2004, before the band made their final attempt at recording what would become Don't Believe the Truth.

Oasis were an English rock band formed in Manchester in 1991. Originally known as the Rain, the group initially consisted of Liam Gallagher, Paul Arthurs (guitar), Paul McGuigan and Tony McCarroll (drums), with Liam's older brother Noel Gallagher joining as a fifth member a few months after their formation. Noel became the de facto leader of the group and took over the songwriting duties for the band's first four albums. They are characterised as one of the defining groups of the Britpop genre.