NSF Acting Director, Chief of Staff to Exit

National Science Foundation Acting Director Brian Stone and Acting Chief of Staff Rebecca Keiser will leave the agency in the coming months. Stone plans to leave at the end of the year and Keiser at the end of the month, according to an agency staff memo. Agency leaders will be “working closely with the White House” to identify a new acting director if President Donald Trump’s nominee is not confirmed by Jan. 1, the memo says.

The high-profile departures could add to the current leadership vacuum at NSF. Stone has served as the face of the agency since the early days of the administration, a particularly tumultuous period for NSF. Keiser has taken on a more prominent role internally; she previously served as NSF’s chief of research security.

NSF spokesperson Mike England confirmed Stone’s and Keiser’s retirements and said the agency will announce any future leadership updates as they are available.

NSF’s last confirmed director, Sethuraman Panchanathan, resigned in April 2025 as grant terminations began to pick up at the agency. Since then, Stone has overseen the agency through:

• More than a thousand additional grant terminations,
• Deep proposed budget cuts,
• Changes to Graduate Research Fellowship Program eligibility,
• Efforts to “dismantle” the National Center for Atmospheric Research,
• The firing of the National Science Board,
• The move to a new headquarters building,
• Moves to implement a controversial OMB-proposed rule on federal grantmaking,
• Participation in the Genesis Mission, and
• New initiatives such as X-Labs and graduate fellowships in partnership with industry.

Agency observers have suggested that the absence of a Senate-confirmed director has made NSF more subject to the direction and priorities of the White House.

Stone’s departure could put pressure on the Senate to act on President Trump’s nomination of Jim O’Neill to be NSF’s next director, which has been stalled since March. Democrats and scientific societies have urged the Senate Health Committee to hold a hearing to determine whether O’Neill is qualified to lead the agency.

“If confirmed, Mr. O’Neill would be the first Director in NSF’s 76-year history who is not a scientist or an engineer, as he lacks both a technical degree and any research experience,” House Science Committee Ranking Member Zoe Lofgren (D-CA) said in a news release.

Stone served as chief of staff for over a decade and has been at the agency a total of 26 years. Keiser served as the agency’s inaugural chief of research security. She held the position for nearly six years, totaling more than 11 years at NSF.

Rob Moller, head of the Office of Legislative and Public Affairs, will serve as acting chief of staff after Keiser’s departure, the memo says.

Departures across the agency

The departures are the latest in a host of staff losses across all levels of the agency. Since the start of the second Trump administration, NSF has lost more than one-third of its staff, according to August data from the White House Office of Personnel Management. About half of those losses came from last year’s deferred resignation program (DRP), which the administration used to incentivize federal workers to leave by continuing to pay full salaries for several months after employees resigned. Meanwhile, non-DRP staff departures have continued to increase this year.

England said NSF “continues to aggressively pursue hiring under its approved hiring plan.” Since January 2025, the agency has lost more than 600 staff and gained 50.

With Keiser’s departure, it is unclear whether NSF’s research security office meets its legally required staffing levels. The CHIPS and Science Act requires NSF to employ a chief of research security and four full-time staffers. As of last December, the agency seemed to be struggling to meet those requirements. Keiser testified that the office had four total staffers, including herself, and that her time was split between the office and the acting chief of staff position. Before the second Trump administration, the office had seven people, Keiser said.

“We have been concerned about this reduction across the foundation,” Keiser said in her testimony before the House Science Committee. “We have lost quite a few staff members.”

NSF ran a search for a new research security chief from Oct. 2 to Oct. 19. The agency said it is currently reviewing candidates. Dean Evasius is serving as both acting chief and acting deputy head of the office in the meantime. Evasius has also been a senior advisor in the Office of the Director since 2024.

Keiser has been the face of NSF’s research security efforts since 2020, when the agency created the position as part of a government-wide push to protect federally funded research, particularly from China.

Under Keiser, the agency has worked to implement National Security Presidential Memorandum (NSPM)-33, a White House document from 2021 that establishes government-wide disclosure standards. NSF also launched programs to fund academic research on research security, mitigate risks for proposals that are close to being funded, and provide scientists with relevant resources.