Songfacts®:

• During the mid 1960s, Petula Clark and her main songwriter, Tony Hatch, mostly recorded in London, but occasionally she would lay down some tracks in LA or New York. Petula recalled to us that on those occasions there would be a kind of excitement, because, "Hey, we've got Tony Hatch and Petula Clark in the studio!"
  
  This song was recorded in New York and Petula was surprised that the drummer, who was the city's top stickman, appeared to be nervous. She recalled to us: "I looked at him and I said, 'What's wrong?' He said, 'I don't know if I can get that London sound.' I said, 'What London sound?' He said, 'Well, you know, that sound...' I said, 'No, I don't actually.' I said, 'Why don't you just play it? That will be fine.'"
• The song proved fairly successful in the US, peaking at #16, but flopped in Clark's native UK. The accompanying Colour My World album was similarly overlooked upon its January 1967 release. However after a month the original edition of the LP was withdrawn in the UK because of the chart success of "This Is My Song" and was re-issued with "This Is My Song" and "The Show Is Over" replacing her covers of "England Swings" and "Reach Out I'll Be There." It went onto become one of Clark's highest charting UK albums.
• Despite its failure in the charts, the song gained a high profile in the UK by virtue of being used by BBC Television as the theme song for the July 1967 launch of its color service.
• A version by Reneé Cologne was used as a jingle in US television commercials for M&M's in 2004. Four years later, UK furniture retailer DFS used the original Petula Clark song in a UK television advertising campaign.
• The song featured, with some additional lyrics, in the stage musical Priscilla Queen of the Desert, which debuted October 6, 2006. It also appears on the 2007 cast recording.