She worked as an education inspection at the Ministry of Trade's Supervision of the Business School in 1959 and was an associate professor of economics and statistics at the Social College in Copenhagen [da] in 1964.
[1] She was the daughter of the civil engineer Hans Georg Koefoed and Frida Rigmor Harriet Heiberg Møller.
[3] Until 1994, Bjørnsen was a member of the board of Kofoeds School and advised department of the Government of Denmark on the International Labour Organization until the late 1960s.
Bjørnsen acted as a go-between in an agreement with sailors and shipowners in 1981 and mediated in the fields of banking and journalism.
[4] Bjørnsen was elected to serve a single term of the Gentofte local municipal council in 1982 after drawing up the cross-party list.
[1][3] Bjørnsen was also chair of the board of Top Danmark Fonden from 1985 to 1990 and led the Education Committee for Special Workers between 1985 and 1993.
[4][5] For her ability to settle disputes, Bjørnsen was made chair of the Danish Writers' Association [da; no; sv] in 1991 to help form internal compromises.