Lagerfelt was consultant at the Volvo International Development Corporation from 1978 to 1979 and was chairman of the parliamentary Inter-American Development Bank investigations from 1980 to 1982. He was also deputy counsel and expert in the United Nations General Assembly in 1967, 1976 and 1977.
Lagerfelt served as a consultant at the Volvo International Development Corporation from 1978 to 1979, and chaired parliamentary investigations into the Inter-American Development Bank from 1980 to 1982. He also worked as deputy counsel and expert in the United Nations General Assembly in 1967, 1976, and 1977.