[4] On July 13, 2017, Prime Minister Justin Trudeau announced that Queen Elizabeth II had approved the appointment of Payette as the next governor general of Canada.

From 1988 to 1990, as a graduate student at the University of Toronto, she was involved in a high-performance computer architecture project and worked as a teaching assistant.

At the beginning of 1991, Payette joined the communications and science department of the IBM Zurich Research Laboratory in Switzerland, for a one-year visiting scientist appointment.

In preparation for a space assignment, Payette obtained her commercial pilot licence and logged 120 hours as a research operator on reduced gravity aircraft.

[27] During 2011–2013, she worked at the Woodrow Wilson International Center for Scholars in Washington, D.C., and was also a scientific delegate to the United States for the Quebec Government.

[28][29][30] For the next three years, Payette was chief operating officer of the Montreal Science Centre of the Société du Vieux-Port de Montréal.

[34] Prior to her departure numerous employees came forward alleging verbal abuse that created a hostile working environment, as Payette was "intimidating" and "determined to be very hands-on and in control of every aspect".

[38] After the announcement was made, Johnston issued a statement congratulating Payette and welcoming "a Canadian of extraordinary achievement, admired by all".

"Anyone can accomplish anything and rise to the challenge as long as they are willing to work with others, to let go of the personal agenda, to reach a higher goal and to do what is right for the common good.

[41] As she was completing her first year as the viceregal representative in September 2018, Payette faced some criticism about controversial comments she had made against those who believe in creationism and those who did not believe in climate change.

[46] In subsequent comments, Payette emphasized the importance of debate and critical thinking but admitted that she was still growing into her role and needed more time to adapt to the position.

"[48] Weeks later, she faced criticism about her work ethic, with some suggesting that she had not devoted enough time and dedication to the role of governor general, noting that she had not visited several of the provinces in her nearly 12-month tenure.

[52] On September 27, Payette acknowledged the articles that had painted an "unfavourable image of our work" in an e-mail to staff, expressed regret about the effect of the criticisms on morale, and assured them that she was "very proud of all we have achieved together to date".

[53] It was reported that the spending included around $140,000 on "studying and designing a private staircase that was never built" and $117,500 on "a gate and series of doors to keep people away from Payette's office".

On July 21, 2020, CBC News reported that Payette had allegedly created a toxic work environment at Rideau Hall by verbally abusing employees.

[55] Two days later, spurred on by the CBC News report, the Privy Council Office formally launched an investigation into her conduct.

[8] The Privy Council Office's independent report found that Payette presided over a toxic work environment, detailing "yelling, screaming, aggressive conduct, demeaning comments and public humiliations.

"[7] On January 21, 2021, in what CBC News described as "an unprecedented move", Payette announced her resignation as governor general (which was effective the following day) after the completion of an independent workplace review of several claims of workplace harassment (in the form of, "belittling, berating and publicly humiliating" staff), as remaining in her post "would risk inflicting serious damage on the office".

[60] Trudeau was criticized by 15 sources interviewed by the CBC for failing to vet Payette properly, as the PMO did not conduct checks with Payette's past employers (Montreal Science Centre and Canadian Olympic Committee) that could have uncovered that her style and temperament were unsuited for the diplomatically sensitive and public role of Governor General.

Carleton University academic Philippe Lagassé has speculated that Payette's decision to resign may have been motivated by her desire to protect her entitlements, as Parliament would be unlikely to retroactively reduce them.

[68] These incidents raised questions on the vetting process as she had been selected by Prime Minister Trudeau without consulting an ad hoc committee of experts.

Such a committee was the means by which outgoing Governor General David Johnston had been selected by the Conservative government of Stephen Harper.