Christianson studied Chemical Engineering at the Universidad Iberoamericana (1966) and the Master of Business Administration at the Stanford University in the United States.
From 1970-1972 he worked for Citibank Mexico as Deputy Director of Planning. In 1972 he joined Inter Leases where he was Director of Credit.
In 1973 he joined the Christianson company as Technical Director, of which he was CEO from 1987 until the sale of the company in 2000 to the Swiss company Clariant. Christianson was one of the leading manufacturers of surfactants in Mexico.
Lars Christianson was president of the National Association of Chemical Industry of Mexico from 1982 to 1984. He received the National Prize for Chemistry in 1985.
He has consulted in various organizations such as the National Bank of Mexico, Mexico Horizon Investment Company, Union Carbide, Petrochemical Grupo Beta, Fausto García Asociados, and the Board of the School of Chemistry of the UNAM.