Samuel Knox Skinner was born on June 10, 1938, in Chicago, Illinois. He graduated from the University of Illinois (B.A., 1960) and received his law degree from DePaul University Law School in 1966. Skinner joined the U.S. Army and served as a platoon leader (1960-1961).He worked for IBM until 1968, when President Nixon appointed him assistant U.S. attorney for the northern district of Illinois. President Ford promoted him to U.S. attorney, a position he held for two years (1975-1977). Skinner served on the Department of Justice's White-Collar Crime Commission and the Attorney General's Advisory Committee.

While in private law practice (1977-1989), Skinner served on the Illinois Fraud Prevention Commission (1977-1979), the Illinois Coal Conversion Task Force (1980), the Illinois Capital Development Board (1979-1984), the Regional Transportation Authority (1984-1989), and as the vice-chairman of the President's Commission on Organized Crime (1983-1985). President George H. W. Bush nominated Skinner to be secretary of transportation, and the Senate unanimously confirmed him on January 31, 1989. Skinner resigned the post in 1991 to become chief of staff to President Bush. Following his time in government, Skinner became president of Chicago-based Commonwealth Edison Company and remained in that post until 1998. Thereafter, he held a number of positions, sitting on the boards of the LTV Corporation and the ANTEC Corporation and serving as president and chief executive officer of USFreightways Corp. Skinner is also a capital partner and co-chairman of Hopkins & Sutter, a Chicago-based law firm.