From 1971–1973 he worked at Addenbrooke's Hospital, Cambridge, as Honorary Senior Registrar and Transplant Fellow under Sir Roy Yorke Calne.
He returned to Sweden and in 1974 joined the Department of Surgery, Sahlgrenska University Hospital, headed by Lars-Erik Gelin.
[3] At the same time he collaborated with Ethan M.Shevach as visiting scientist at the National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland.
In 1998, Bitter-Suermann was elected to the Nova Scotia House of Assembly, defeating Liberal cabinet minister Jim Barkhouse by 110 votes in the Chester-St. Margaret's riding.
[4][5] Elected as a member of the Progressive Conservatives, Bitter-Suermann broke party ranks in June 1998 to vote against the Liberals minority government budget.
[6][7] In October, he quit the Progressive Conservative caucus to sit as an independent member,[8] before crossing the floor in November to join the Nova Scotia New Democratic Party.