She began her professional career as a model before being noticed by a talent scout and being signed to a film contract in 1932 by RKO Studios.

She filled in for an actor to promote Westinghouse products during the advertisement break, and impressed the company with her easy and professional manner.

Making $150 a week at first, Furness did three Westinghouse commercials (they were the sole sponsor of the show) for every episode of Studio One, all of them shot live, since videotape did not yet exist.

(One live spot featured a refrigerator door that refused to open, causing one of the most famous bloopers in TV history; however, this was not Furness, but actress June Graham, who was substituting for her.

)[3] Furness proved a successful spokeswoman because of her good looks and attractive, but neat and modest clothing, which she changed three times a day.

She also proved strongly independent-minded about her appearance and image, refusing to adopt a stage name or wear an apron after Westinghouse offered these suggestions.

During the political party conventions in the 1952 presidential election, the television coverage of which was heavily sponsored by Westinghouse, Furness wore 28 different outfits, enough to become the subject of a Life story.

Furness's contract with Westinghouse eventually resulted in her receiving an annual salary of $100,000 and her advertisements caused sales of the company's appliances to soar, with the one notable exception of the dishwasher, which proved a hard sell after market research found that American women were reluctant to buy a device that would in effect completely automate their kitchen and give them nothing to do.

(The spots were so well known they were often parodied: one Mad magazine gag imagined the words on a neon sign, with a few key letters burned out: YOU CAN ..SU.E IF IT'S WESTINGHOUSE!

[5] In 1959, a new Westinghouse president decided to drop Furness, possibly because he wished to impose his own ideas on the company, and suggested getting a new, slightly younger spokeswoman.

[7][8] In 1967, President Lyndon B. Johnson, aware of her work for the Democratic Party, contacted Furness and offered her the position of Special Assistant for Consumer Affairs.

In 1976 she began an association with The Today Show filling in as anchor following the departure of Barbara Walters and providing regular reports.