Citing medical reasons, Lou D'Ambrosio, president and CEO of Avaya for the past six years, is to step down from the position with immediate effect. He will, however, remain at the company in an advisory capacity.

Computerworld reports that D'Ambrosio will be replaced on an interim basis by Charles Giancarlo, the former chief development officer of Cisco who joined equity firm Silver Lake Partners at the end of last year. Silver Lake and TPG Capital acquired Avaya about a year ago.
Avaya specialises in unified communications products and D'Amrosio was regarded as an aggressive CEO prepared to take on the might of Cisco and Microsoft in this sector.
The company has hired executive search company Hendrick & Struggles to find a successor.