[3] In February 2015, she was appointed chief executive officer for Deloitte Australia, succeeding the previous CEO Giam Swiegers.

In this role Hook oversaw 65,000 professionals and the firm's operations in Australia, China, Japan, Korea, Southeast Asia, and New Zealand.

[10] On December 13, 2022, Hook was appointed as chief executive of the organising committee for the 2032 Summer Olympic and Paralympic Games set to take place in Brisbane, Queensland, Australia.

She also introduced paid parental leave for fathers, and took major steps to enable the advancement of women and ensure pay equality.

[17] In 2017, she was named Pride in Diversity CEO of the Year[18] for her efforts in creating an inclusive atmosphere at Deloitte and championing the LGBTI community.