He was born in Gothenburg, Sweden. Prior to ABBA he was in the Hootenanny Singers. He met Bjorn Andersson in 1966 while in the road and they became friends. He was a member of the group ABBA from when the members first met in 1969. In 1971 he and Agnetha Faltskog were married, having two children, Linda and Christian. They divorced in July 1980. He married Lena Kallersjo on 6^th January 1981 and he had two further daughters, Emma and Anna. He has created the musicals Chess, Kristina fran Duvemala and Mamma Mia with Benny Andersson. He was nominated for a Drama Desk Award for Outstanding Music, for Chess, and a Tony for Best Orchestration for Mamma Mia. He has been nominated for six Grammy awards, winning four. Together with Benny Andersson he was awarded the Ivor Novello Prize. He has also won a Lifetime Achievement Award from the Swedish Music Publishers Association. He is a member of the Swedish Human Rights group Humaninsterna.

Abba Recordings

Take A Chance on Me (Bjorn Ulvaeus/Benny Andersson)

I'm A Marionette (Bjorn Ulvaeus/Benny Andersson)

The Winner Takes It All (Bjorn Ulvaeus/Benny Andersson)

Elaine (Bjorn Ulvaeus/Benny Andersson)

Debby Boone recordings

Hasta Manana (Benny Andersson/Bjorn Ulvaeus/Stig Andersson)

Anne Sofie von Otter recordings

Day before You Came, The (Bjorn Ulvaeus/Benny Andersson)

Heaven Help My Heart (from ''Chess'') (Benny Andersson/Bjorn Ulvaeus/Tim Rice)

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