English progressive rock band Yes has enjoyed a 40-year career and critical acclaim for its blend of classical music structures in its music. The band formed in the late 1960s, and though the lineup has varied over the years, primary members are Jon Anderson (vocals), Chris Squire (bass), Steve Howe (guitar) and Alan White (percussion).

The band had planned the Close to the Edge and Back Tour in summer 2008 to celebrate its 40th anniversary, but plans were scrapped when Anderson was diagnosed with acute respiratory failure and ordered to rest for at least six months. At the end of the year, the band reformed without Anderson, option to tour with Yes tribute band singer Benoit David instead.

The decision irritated Anderson, who claimed he had not been informed of the decision nor visited by his band mates during his convalescence, as well as fans, who felt that the band had no right to tour under the “Yes” name without its iconic singer. However, the tour fared well enough to inspire a 2009 summer tour — still featuring David on vocals — with fellow prog-rock band, Asia, for which Howe also plays guitar.