Göran Bror "Benny" Andersson (born 16 December 1946), known professionally as Benny Andersson , is a Swedish musician, composer, former member of the Swedish music group ABBA (1972–1982), and co-composer of the musicals Chess, Kristina från Duvemåla, and Mamma Mia!. For the 2008 film version of Mamma Mia! he worked also as an executive producer. Since 2001 he is active with his own band Benny Anderssons orkester.