Ianniello started his career at CBS in 1997 as Director of Financial Planning.
His next move within CBS was as its Vice President of Corporate Development from 2000-2005. At that position, Mr. Ianniello was in charge of all financial planning matters at CBS including investor relations. He became Senior Vice President of Finance and Treasurer of Viacom Inc. in July, 2005. During that time, he was involved in many of the mergers and acquisitions including the acquisitions of BET, Comedy Central and Sportsline. He was also involved in the divestiture of Blockbuster.
In December 2015, he served as Senior Vice President of Finance and Treasurer of CBS Corporation.
During the time since, he was Director of Entercom Communications Corporation and Executive VP / Treasurer of CBS Radio Inc.   In 2009, Ianniello served as CBS’s Chief Financial Officer and Executive Vice President of CBS Corporation for four years, where he was responsible for the company’s financial strategy across all of its operations. He was named COO of CBS Corporation in 2013.
In 2017, Ianniello signed a contract extension to June 30, 2022, a year longer than Chairman and CEO Les Moonves. This is significant because, according to the New York Post, Ianniello was being poised to succeed Moonves as CEO at some point in the future. That contract extension includes a $70 million payout if his employment were to end by way of a merger.
CBS Corporation is an American mass media corporation focused on commercial broadcasting, publishing, billboards and television production, with most of its operations in the United States. The company began trading on the NYSE on January 3, 2006. Until then, the corporation was known as Viacom, and is the legal successor to said company. A new company, keeping the Viacom name was spun off from CBS. CBS, not Viacom, retains control of over-the-air television (CBS, CW) and radio broadcasting, TV production and distribution, publishing, pay-cable, basic cable (TVGN), and recording formerly owned by the larger company. CBS has its headquarters in CBS Building, Midtown, Manhattan, New York City, New York, United States.