"I Know Him So Well" is a duet from the concept album and subsequent musical Chess by Tim Rice, Benny Andersson and Björn Ulvaeus. It was originally sung by Elaine Paige (as Florence) and Barbara Dickson (as Svetlana). In this duet, two women – Svetlana, the Russian chess champion's estranged wife, and Florence, his mistress – express their bittersweet feelings for him and at seeing their relationships fall apart.
The chorus of the song is based on the chorus of "I Am An A", a song performed live during Andersson and Ulvaeus' group ABBA's 1977 tour.[2] Although "I Am An A" was never released officially, it circulated on various bootlegs and is readily available on YouTube.
The duet was first released worldwide on the Chess double LP, often referred to as a concept album or album musical, in the autumn of 1984. Later it was released as a single by Paige and Dickson, the duet reaching number one in the UK Singles Chart for four weeks in 1985.[3] They laid down their vocals separately and never met during the recording of the song, only for the video and subsequent performances on Top of the Pops and the European tours.[1][4] This recording remains in the Guinness Book of Records as the biggest selling UK Chart single ever by a female duo. Paige also appeared in the original London West End stage production of Chess. The song peaked at number 21 in Australia.[5]
In the United Kingdom on 18 September 2004, the BBC's All-Time Greatest Love Songs (hosted by Lionel Richie) saw the duet performed live by Paige and Dickson, together for the first time in 20 years, to a rapturous reception. Paige played her solo demo recording of the song on her BBC Radio 2 show, Elaine Paige on Sunday.
In January 2011 the Official Charts Company released a list of the top 10 All Time Best Selling Duets in which "I Know Him So Well" was placed seventh in the chart.[6]
Paige and Dickson also recorded Spanish-language lyrics for release as "Lo Creo Conocer". The single was never released though.[7]