DOE/LANL Jurisdiction Fire Danger Rating:
Leadership Marquee
  1. LANL Home
  2. About the Lab

Leadership and Governance

Los Alamos National Laboratory’s Leadership

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 December 2025

Download the LANL Leadership Org Chart (PDF). 

Laboratory Director’s Office

Thom Mason Director Card

Thomas Mason

Laboratory Director

Read More
Francis Chadwick Staff Director Card

Frances Chadwick

LANL Staff Director

Read More
Pat Fitch Ddste Card

J. Patrick Fitch

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

Read More
Bob Webster Ddw Card

Robert Webster

Deputy Laboratory Director for Weapons (DDW)

Read More
Mark Davis Ddops Card

Mark Davis

Deputy Laboratory Director for Operations (DDOPS)

Read More

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

Ellen Cerreta Aldps Card

Ellen K. Cerreta

Associate Laboratory Director, Physical Sciences (ALDPS)

Read More
Mark Chadwick Aldsct Card

Mark B. Chadwick

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

Read More
Srinivas Iyer Aldcels Card

Srinivas Iyer

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

Read More
Nancy Jo Nicholas Aldgs Card

Nancy Jo Nicholas

Associate Laboratory Director, Global Security (ALDGS)

Read More

Associate Laboratory Directors for Weapons (DDW)

Mark Anthony Aldpi Card

Mark Anthony

Associate Laboratory Director, Plutonium Infrastructure

Read More
David Dooley Aldwp Card

David Dooley

Associate Laboratory Director, Weapons Production (ALDWP)

Read More
John Hill Aldw Card

John A. Hill

Associate Laboratory Director, Weapons Engineering (ALDW)

Read More
Charlie Nakhleh Aldx Card

Charles W. Nakhleh

Associate Laboratory Director, Weapons Physics (ALDX)

Read More

Associate Laboratory Directors for Operations (DDOPS)

Scott Aeilts Aldbus Card

Scott Aeilts

Associate Laboratory Director, Business Management

Read More
Unica Viramontes Alddp Card

Unica K. T. Viramontes

Associate Laboratory Director, Defense Protection (ALDDP)

Read More
Steven Coleman Aldeshq Card

Steven Coleman

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

Read More
Bret Simpkins Aldfo Card V4

Bret Simpkins

Associate Laboratory Director, Facilities & Operations (ALDFO)

Read More
Jeff Sims Aldicp Card

Jeff Sims

Associate Laboratory Director, Infrastructure & Capital Projects (ALDICP)

Read More