[3] After the 2016 Presidential election, she became a partner in the Silicon Valley office of an international law firm, where her practice focused on strategic consulting and crisis management.

[4] Over her career, O'Leary has helped to establish several non-profit organizations promoting progressive policy on income inequality, health care, education, and workforce development.

[11][15] She oversaw a "wide range of issues,"[16] including passage of the 9/11 Victims Compensation Fund and the Medicare Prescription Drug, Improvement, and Modernization Act.

[17] As a deputy city attorney, she helped develop the strategy to combat predatory lending practices by payday lenders, which resulted in a $7.5 million settlement for low-income victims.

[18] In 2008, O'Leary was appointed as a Lecturer and the founding executive director of the Center on Health, Economic & Family Security at the University of California, Berkeley School of Law.

[22] In 2011, O'Leary was appointed as a senior vice president at Next Generation, a non-profit organization promoting progressive policy to address economic inequality and climate change.

[31] She has advised multiple high-profile organizations, including the Silicon Valley Community Foundation as it investigated and navigated allegations of a toxic work environment.

[32] A team of lawyers led by O'Leary published a report that found "many allegations from current and former employees were substantiated," and made recommendations for reform that were adopted by the Foundation's board in full.

[37] In this role, O’Leary has championed several key administration initiatives, including an increase in California's earned income tax credit,[38] expanded child care and paid family leave,[39] subsidies to help families afford health insurance,[40] new investments to build housing and reduce homelessness,[41] and the promotion of civil rights, including Newsom's decision to halt capital punishment in the state.