O'Leary's tenure as U.S. Secretary of Energy ended, coinciding with the close of the first Clinton administration.
On January 20, 1997, Hazel R. O'Leary concluded her four-year tenure as U.S. Secretary of Energy, coinciding with the end of President Bill Clinton's first term in office. Her departure marked the close of a historically significant chapter for the Department of Energy.
During her time in office from 1993 to 1997, O'Leary had overseen sweeping changes to the department's culture, most notably through her Openness Initiative, which declassified millions of pages of documents related to nuclear weapons testing and human radiation experiments. She also advocated for renewable energy development and engaged with nuclear testing regulation issues during a critical post-Cold War period.
Her departure from the Cabinet did not end her public influence; O'Leary went on to found O'Leary & Associates, a consulting firm, and later became a senior executive at Blaylock and Partners before eventually returning to academia as president of Fisk University.
Her legacy as Secretary of Energy is widely regarded as one of institutional transformation, having shifted the department toward greater transparency, accountability, and public engagement — a legacy still referenced in discussions of government transparency and Department of Energy history today.