Telstra's chief operations officer Kate McKenzie will retire from the telco after 12 years with the business and three years leading its network architecture and operations, IT, and field services.
McKenzie today said "the time is right" for her to "change direction" in her career.
It is understood McKenzie will be looking for non-executive director roles, as well as opportunities for mentoring young women and in the start-up community.
She will retire from the telco "in the coming weeks" and will be replaced in the interim by enterprise and services chief Brendon Riley while Telstra searches for a permanent replacement.
Telstra CEO Andy Penn said McKenzie had been a "positive force" during her tenure with the company.
"She has been a significant contributor to our customer-focused culture and a role model for women in the organisation. I have appreciated her support and counsel," Penn said in a statement.
McKenzie first joined Telstra in 2004 as head of its regulatory group, and quickly worked her way up the ladder - first as deputy head of public policy and communications, then head of strategic marketing before being promoted to lead Telstra Wholesale.
She took on her current role in October 2013, leading operations, the chief technology office, and Telstra's innovation portfolios.
Most recently her time has been spent dealing with the fallout from a series of outages that rocked the telco in the first six months of this year.
The problems prompted McKenzie and the telco to announce a $50 million injection into Telstra's network - to go towards real-time traffic monitoring and customer impact reporting kit, and improving capacity following a mass disconnection - to avoid a repeat of the damaging outages.