In a move that took the industry by surprise Carly Fiorina announced today that after "differences" with HP's board of directors she has stepped down as chairman and chief executive, effective immediately.

Chief financial officer Robert Wayman has been named chief executive on an "interim basis" and appointed to the board of directors. Patricia Dunn has been named non-executive chairman of the board, also effective immediately.

"While I regret that the board and I have differences about how to execute HP's strategy, I respect their decision," said Fiorina.

The HP board will begin a search for a new chief executive immediately. Wayman, a 36-year veteran of the company, will also retain his chief financial officer responsibilities.

The company does not expect to make any additional structural or executive leadership changes at this time.