Veteran Wall Street lawyer Jay Clayton was formally sworn in as chairman of the U.S. Securities and Exchange Commission (SEC) on Thursday.

Clayton was nominated to the post by U.S. President Donald Trump back in January and confirmed by Congress earlier this week.

Clayton comes to the SEC from New York-based law firm Sullivan & Cromwell LLP, where he was a partner, specializing in mergers and acquisitions, securities offerings, along with other capital markets issues. From 2009 to 2017, he also served as an adjunct professor at the University of Pennsylvania Law School, teaching a class on M&A, among other things. He is a member of the bar in New York and Washington, D.C., and has degrees in engineering and economics, in addition to law.

“It is a tremendous honour to lead the SEC and to be sworn in by Justice Kennedy, whom I greatly admire,” said Clayton in a statement. “The work of the SEC is fundamental to growing the economy, creating jobs, and providing investors and entrepreneurs with a share of the American Dream.”

Clayton replaces Michael Piwowar, acting chairman, who has been in the role since January after the previous chairwoman, Mary Jo White, stepped down. Clayton’s term expires on June 5, 2021.