Gattung worked in senior marketing roles at National Mutual and at the
Bank of New Zealand before taking up a similar role at
Telecom New Zealand. In April 1996, she became Telecom's Group General Manager Services. In October 1999, she took over from
Rod Deane as Telecom's
CEO of the telecommunications business with a $5 billion turnover operating in New Zealand and Australia and listed on the NZX, ASX and NYSE. Gattung was the first woman to run a large New Zealand public company. During her tenure as CEO Gattung led Telecom through world-changing technology developments and the evolution of the business from a traditional telco to the number one IT provider in New Zealand. Gattung resigned her position at Telecom in 2007. Following her passion for books and reading Gattung was also the chair of the New Zealand Advisory Group for the Frankfurt Book Fair 2012. In 2013, Gattung, alongside Cecilia Robinson and
Nadia Lim, co-founded food delivery business
My Food Bag. Operating in New Zealand the company grew very quickly with turnover exceeding $150 million. Gattung chaired insurer AIA Australia 2010 - 2021 and was an Independent Director and Chair of AIA New Zealand's Board of Directors 2018 - 2025.. She was a member of the National Advisory Board on the Employment of Women 2016 - 2025. Gattung also currently chairs Tend, launched mid-2020 with a mission to put digital healthcare in the hands of all Kiwis, the online education content provider Telco Technology Services, Global Women. In 2021, Gattung funded the Theresa Gattung Chair of Women in Entrepreneurship at the University of Auckland and also started the Gattung Foundation with her sister Angela Gattung as executive director of the fund. Gattung has been involved with a number of not-for-profit and philanthropic interests, including being co-founder and trustee of the World Women Charitable Trust, the Eva Doucas Charitable Trust, Patron of the Cambodia Charitable Trust and Chair of the Wellington Board of the
Society for the Prevention of Cruelty to Animals (SPCA) and then on the Royal New Zealand SPCA (RNZSPCA) National Board when all the regions joined to form a National body. She was NZ Lead for SheEO (now Coralus) 2017 - 2022, a radically redesigned ecosystem that supports, finances, and celebrates female innovators. The
Arts Foundation of New Zealand partnered with Gattung in 2019 to add a $25,000 Arts Laureate prize of the Theresa Gattung Female Arts Practitioners Award. In 2010, Gattung published an autobiography,
Bird on a Wire. == Awards and recognition ==