[6] Parker began attending Rice University on a National Merit scholarship in 1974, working several jobs to pay for her room and board.

In addition, she co-owned Inklings Bookshop with business partner Pokey Anderson from the late 1980s until 1997 and served as president of the Neartown Civic Association from 1995 to 1997.

"[14] In 2009, Parker announced her candidacy for the office of Mayor of Houston in a video posted online to her campaign website.

[16] Other people who were in the running for mayor included Houston City Council Member Peter Hoyt Brown and Harris County school board trustee Roy Morales; they were eliminated from the race on November 3, 2009.

[17][18] After the election, Parker declared that the top priorities of her administration would be improving transportation, balancing the city's budget, and selecting a new police chief.

[19] In the 2011 election, Parker won a second term as Houston's Mayor by defeating Fernando Herrera, Jack O'Connor, Dave Wilson, Kevin Simms, and Amanda Ulman without a runoff.

In November 2013, Parker won a third term as Houston's Mayor by winning 57.22% of the vote, making a runoff unnecessary.

Mayor Parker had certified that "there exists a public emergency requiring that this Ordinance be passed finally on the date of its introduction".

[21] In response, city attorneys defending the law filed subpoenas for sermons from local Christian pastors.

[34] As mayor, Parker voted for and then enacted an ordinance making it illegal to share food with the homeless in public spaces.

[35] Lawsuits continue over the ordinance, with a judge ruling in 2024 that local organization Food Not Bombs Houston could sue the city over it.

[44] In June 2020, in honor of the 50th anniversary of the first LGBTQ Pride parade, Queerty named her among the fifty heroes "leading the nation toward equality, acceptance, and dignity for all people.