Maurice Sonnenberg is a senior American intelligence and financial advisor.
He started his career as an aide to Democratic Senator William Proxmire of Wisconsin, who headed the Senate Banking Committee. He had campaigned for the Lyndon B. Johnson-Hubert Humphrey ticket in the presidential election of 1964, where he first met J. Bruce Llewellyn. In 2008, he donated US$114,550 to Democratic candidates, including David Price, Mark Begich, Charles B. Rangel, Carl Levin, Dan Maffei, Byron Dorgan, Nita Lowey, Mark Warner, Kirsten Gillibrand, Frank Lautenberg, Jay Rockefeller, Mark Pryor, Max Baucus, Nancy Pelosi, Chris Dodd, Bill Richardson, Joe Biden, Hillary Clinton, and Barack Obama.
In 1994 and 1995, he served as a member of the Moynihan Commission on Government Secrecy, and in 1996 as Senior Advisor to the Aspin–Brown Commission. He was a member of the President's Intelligence Advisory Board under President Bill Clinton.