The catchy concept of "leaving loudly" was introduced as part of a broader push in the past 12 months to bring more flexibility to the Westpac workforce.
"We do focus on making sure that the flexibility is working for the individual but also for the team and the organisation. At the heart of that is our customers, so it's making sure that we communicate regularly."
Dellabarca said the shift had really driven staff retention and made easier to attract good talented people to the company.
She said there was no evidence of any loss of productivity.
"It hasn't become a trade-off for those people, for what they get paid or their career progression," she said. "The key is we can get the best out of people and they feel they're getting the best out of their work."
It was important have the tone set from the top, Dellabarca said.
"Making sure that executives and senior managers are living and breathing flexibility as well, actually helps people to see that its running right through the organisation."
Westpac had been focused for some time on policies of diversity and inclusion and had a women's leadership programme, she said.
"That's probably been a tipping point for us with the amount of women in leadership across Westpac, particularly at senior levels where it has helped push forward some these flexibility policies.
Ultimately though the policy benefited everybody, she said.
"What we've found is as many men have benefited as women."
