The news came this morning from NBC news chairman Andy Lack.
In a memo to NBC employees, Lack said the decision to fire Lauer was made after an employee filed a complaint about "inappropriate sexual behavior in the workplace."
Lack went on to say that while it was the first complaint lodged against Lauer in his career at the network, the company was "presented with reason to believe this may not have been an isolated incident."
Lauer’s one time co-host Savannah Guthrie made the announcement at the top of the Today Show, where Lauer has been an anchor for two decades.
Guthrie said she was informed just moments before going on the air.
Lauer did not immediately respond publicly to the announcement of his firing. NBC News has reached out to his reps for comment.