In 1981, he became Chief of Staff to Prime Minister Laurent Fabius in his various government posts (Budget Minister, Minister for Industry and Research and Prime Minister).
He joined Renault in 1986 and became Chief Financial Officer and Head of Strategic Planning in 1988.
He was appointed Executive Vice President and COO in 1989, and President and COO in 1990.
He was Renault's Chairman and CEO from May 1992 to April 2005, and president of the Renault-Nissan Alliance Board from 2001 to 2005.
On 29 April 2005, he became Chairman of the Renault Board of Directors.
In 1995, the Justice Ministry investigated Schweitzer for being an "accomplice in poisoning" of the hemophiliacs.
The case stemmed from his tenure as Chief of Staff to Laurent Fabius and whether he knowingly allowed blood infected with HIV to be distributed to recipients.