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Leadership and Governance

Los Alamos National Laboratory’s Leadership

Leadership Group Photo August 2026

The Leadership Team is fully committed to enabling the Laboratory’s mission while supporting its people, further enhancing the culture, and meeting the goals outlined in the Lab Agenda.

Our leaders are committed to scientific and technological excellence, driving a culture of operational excellence, and enabling the high quality and integrity of the Laboratory’s national security missions.

Lanl Leadership Org Chart

Download the LANL Leadership Org Chart (PDF). 

Laboratory Director’s Office

Thom Mason Director Card

Thomas Mason

Laboratory Director

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Francis Chadwick Staff Director Card

Frances Chadwick

LANL Staff Director

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Pat Fitch Ddste Card

J. Patrick Fitch

Deputy Laboratory Director for Science, Technology & Engineering (DDST&E)

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Charlie Nakhleh Aldx Card

Charles W. Nakhleh

Deputy Laboratory Director for Weapons (DDW)

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Mark Davis Ddops Card

Mark Davis

Deputy Laboratory Director for Operations (DDOPS)

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Associate Laboratory Directors for Science, Technology & Engineering (DDST&E)

Ellen Cerreta Aldps Card

Ellen K. Cerreta

Associate Laboratory Director, Physical Sciences (ALDPS)

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Mark Chadwick Aldsct Card

Mark B. Chadwick

Associate Laboratory Director, Simulation, Computing & Theory (ALDSCT)

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Srinivas Iyer Aldcels Card

Srinivas Iyer

Associate Laboratory Director, Chemical, Earth & Life Sciences (ALDCELS)

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Nancy Jo Nicholas Aldgs Card

Nancy Jo Nicholas

Associate Laboratory Director, Global Security (ALDGS)

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Associate Laboratory Directors for Weapons (DDW)

Mark Anthony Aldpi Card

Mark Anthony

Associate Laboratory Director, Plutonium Infrastructure

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David Dooley Aldwp Card

David Dooley

Associate Laboratory Director, Weapons Production (ALDWP)

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John Hill Aldw Card

John A. Hill

Associate Laboratory Director, Weapons Engineering (ALDW)

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John Scott Aldx

John Scott (Interim)

Associate Laboratory Director, Weapons Physics (ALDX)

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Associate Laboratory Directors for Operations (DDOPS)

Scott Aeilts Aldbus Card

Scott Aeilts

Associate Laboratory Director, Business Management

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Unica Viramontes Alddp Card

Unica K. T. Viramontes

Associate Laboratory Director, Defense Protection (ALDDP)

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Steven Coleman Aldeshq Card

Steven Coleman

Associate Laboratory Director, Environment, Safety, Health & Quality (ALDESHQ)

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Bret Simpkins Aldfo Card

Bret Simpkins

Associate Laboratory Director, Facilities & Operations (ALDFO)

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Jeff Sims Aldicp Card

Jeff Sims

Associate Laboratory Director, Infrastructure & Capital Projects (ALDICP)

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(505) 667-5061

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