Before becoming governor-general, Reddy was a partner of a law firm, headed a major review of intelligence agencies, held multiple directorships, chaired the New Zealand Film Commission and worked as a chief negotiator on Treaty of Waitangi settlements.

[3] Reddy was raised in the small Waikato towns of Te Ākau and Minginui until her family moved to Hamilton when she was six years old.

She later took up a position at Brierley Investments, where she was employed for 11 years, and worked on large acquisition negotiations such as the privatisation of Air New Zealand.

[5] Reddy served as chair of the New Zealand Film Commission and Education Payroll Ltd and was a director of Payments NZ Ltd and Active Equity Holdings Ltd. She was a chief Crown negotiator for Treaty of Waitangi settlements and a lead reviewer for the Performance Improvement Framework for the State Services Commission.

[6] In 2016, Reddy and Sir Michael Cullen collaborated on an independent report to the New Zealand government reviewing legislation covering the country's intelligence agencies.

[13] In March 2016, it was announced that Queen Elizabeth II had approved the appointment of Reddy as the next governor-general of New Zealand, for a five-year term starting in September 2016, on the advice of then Prime Minister John Key.

The swearing-in ceremony included a Māori pōwhiri, a 21-gun salute, and music from the Royal New Zealand Air Force Band and the New Zealand Opera Chorus; the ceremony was attended by hundreds of observers, including film-makers Sir Peter Jackson and James Cameron (a former neighbour), with an address by Prime Minister John Key.

[21] In her first overseas trip, Reddy visited Niue and the Cook Islands, the associated states of New Zealand, on 21 and 22 March 2017 respectively.

[24] On 30 September 2017, Reddy travelled to Israel for a two-day trip, in which she represented New Zealand at official commemorations to mark the centennial of the Battle of Beersheba during the First World War.

[28] On 24 October 2017, Reddy hosted a state welcome for the president of Ireland, Michael D. Higgins, at Government House.

[29] A couple of weeks later, Reddy hosted German President Frank-Walter Steinmeier at Government House from 5 to 7 November 2017.

[37] On 3 December she welcomed the President of the Republic of Korea, Moon Jae-in and his wife Kim Jung-sook to New Zealand during a ceremony at Auckland Government House.

[39] On 7 June 2019, Reddy represented New Zealand at the commemorations for the 75th anniversary of the D-Day landings at Portsmouth in the United Kingdom.

[46] In the 2014 Queen's Birthday Honours, Reddy was appointed a Dame Companion of the New Zealand Order of Merit for services to the arts and business.

[50][51] Victoria University of Wellington conferred an honorary Doctor of Laws degree on Reddy on 13 December 2017.