From 1957–1964, she was a scientific assistant at the Norwegian Institute of Local History (Norsk lokalhistorisk institutt).
She was a member of the Norwegian Academy of Sciences from 1994 and head of the International Commission for Historical Demographic Research (ICHD).
She was a board member of the Norwegian Institute of Local History (1978-1981) and chairman (1982-1993).
Norsk ungdom over Nordsjøen til Nederland i tidlig nytid (1994) and Og skuta lå i Amsterdam-: et glemt norsk innvandrersamfunn i Amsterdam 1621-1720 (2012) in which she researched 17th century Norwegian immigration to Amsterdam and to the Netherlands.
She wrote about the period 1500–1750 in Cappelens kvinnehistorie (1992), and volume 6 ("Krig og fred 1660–1780") in Aschehougs Norgeshistorie (1996).