The song was written by Steve Mac and co-written by Ina Wroldsen and Rhys Barker, who has previously worked on the band's singles.

The Saturdays collaborated with Ina Wroldsen and Rhys Barker again, The song has prominent electropop, dance-pop and synthpop genre characteristics.

The music video accompanying "Ego" was directed by Mike Simpson and Robin Van Calcar and premiered on YouTube on 17 November 2009.

Once we finished writing the song together, Ina laid a guide vocal over the top of the keyboard sound and then went away and left me and Rhys to do the rest of it.

[3] Carla Pearce of FemaleFirst mentioned that the single "Combines infectious synthesised riffs with a thumping beat to create a riot of a track that will no doubt become another smash hit.

"[4] Nick Levine of Digital Spy award the song 3/5 stars describing the chorus as "catchy enough".

They went on to say, "The heavy beat is the first thing to strike you, as the girls warble away chanting: "You need to have a sit down with your ego!"

The second week of January, "Ego" placed itself at number 10 on the Irish Singles Charts, becoming the band's third top 10 hit in the country.

The music video was directed by Mike Simpson & Robin Van Calcar and produced by MrsGrey productions.

The male, main role in the music video is played by Waz Ashayer, who is a model, and became famous after appearing on Make Me a Supermodel.

As the video starts, Vanessa is seen singing to a picture of what appears to be a superhero team made of the Saturdays and an extra male.

As the second chorus kicks in, Vanessa displays telekinetic power, being able to pull and push the man around from a distance.

The video closes with the Saturdays walking calmly down a deserted road with the man crawling pathetically backwards from the girls.

They later appeared BBC Switch Live, to promote the newly single, which gained a lot of downloads for the song.

They appeared on late night talk-show, Alan Carr: Chatty Man, and performing in front of thousands on Dancing on Ice.