I lead the alignment team at Anthropic, where I'm hoping to reduce existential risks from AI systems. I led the team that developed Constitutional Classifiers, the first approach capable of robustly preventing most bad actors from obtaining harmful information from AI systems; Constitutional Classifiers enabled Anthropic to deploy Claude 4 Opus and subsequent models, despite their ability to assist in advanced weapons development. I helped to develop Retrieval-Augmented Generation (RAG), a widely used approach for augmenting large language models with other sources of information. I also introduced Automated Red Teaming, which is used across major frontier AI labs for pre-deployment model testing. I received a best paper award at ICML 2024 for my work showing that debating with more persuasive models leads to more truthful answers.

I received my PhD from NYU under the supervision of Kyunghyun Cho and Douwe Kiela, funded by the National Science Foundation and Open Philanthropy. Previously, I've spent time at DeepMind, Facebook AI Research, University of Montreal, Uber, and Google. I was also named one of Forbes's 30 Under 30 in AI.

Ethan's Research

Authors
Roger Grosse, Juhan Bae, Cem Anil, Nelson Elhage, Alex Tamkin, Amirhossein Tajdini, +9 more, Samuel R Bowman, Ethan Perez
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Tamera Lanham, Anna Chen, Ansh Radhakrishnan, Benoit Steiner, Carson Denison, Danny Hernandez, +22 more, Samuel R Bowman, Ethan Perez
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Ansh Radhakrishnan, Karina Nguyen, Anna Chen, Carol Chen, Carson Denison, Danny Hernandez, +16 more, Samuel R Bowman, Ethan Perez
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Ian R. McKenzie, Alexander Lyzhov, Michael Pieler, Alicia Parrish, Aaron Mueller, Ameya Prabhu, +19 more, Samuel R. Bowman, Ethan Perez
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Deep Ganguli*, Amanda Askell*, Nicholas Schiefer, Thomas I. Liao, Kamile Lukošiute, Anna Chen, +41 more, Samuel R. Bowman, Jared Kaplan
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Ethan Perez, Sam Ringer*, Kamile Lukošiute*, Karina Nguyen*, Edwin Chen, Scott Heiner, +55 more, Nicholas Schiefer, Jared Kaplan
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Samuel R. Bowman, Jeeyoon Hyun, Ethan Perez, Edwin Chen, Craig Pettit, Scott Heiner, +38 more, Ben Mann, Jared Kaplan
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Deep Ganguli, Liane Lovitt, Jackson Kernion, Amanda Askell, Yuntao Bai, Saurav Kadavath, +28 more, Jared Kaplan, Jack Clark
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Alicia Parrish*, Harsh Trivedi*, Ethan Perez*, Angelica Chen, Nikita Nangia, Jason Phang, Samuel R. Bowman
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Jérémy Scheurer, Jon Ander Campos, Jun Shern Chan, Angelica Chen, Kyunghyun Cho, Ethan Perez
Authors
Ethan Perez, Saffron Huang, Francis Song, Trevor Cai, Roman Ring, John Aslanides, Amelia Glaese, Nat McAleese, Geoffrey Irving
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Rajarshi Das, Manzil Zaheer, Dung Thai, Ameya Godbole, Ethan Perez, Jay-Yoon Lee, Lizhen Tan, Lazaros Polymenakos, Andrew McCallum
Authors
Patrick Lewis, Ethan Perez, Aleksandara Piktus, Fabio Petroni, Vladimir Karpukhin, Naman Goyal, +3 more, Sebastian Riedel, Douwe Kiela
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Vincent Dumoulin, Ethan Perez, Nathan Schucher, Florian Strub, Harm de Vries, Aaron Courville, Yoshua Bengio
Authors
Simon Brodeur, Ethan Perez*, Ankesh Anand*, Florian Golemo*, Luca Celotti, Florian Strub, Hugo Larochelle, Aaron Courville

Blog

October 9, 2022

Inverse Scaling Prize Ideas

Written by Alex Lyzhov, Ian McKenzie, and Ethan Perez We collected a list of ideas for tasks to explore that could potentially show inverse scaling! These […]
September 13, 2022

Personal Research Statement
for Ph.D. Programs in Machine Learning

A few people have asked to read my personal research statement for Ph.D. programs in machine learning, so I’ve released my statement here (link). The statement […]
September 5, 2022

Easy Paper Writing Tips

Easy Paper Writing Tips Below are a few paper writing tips that improve the clarity of research papers, while also being fairly easy to implement: Minimize […]
Ethan Perez

Ethan Perez

Head of Alignment · Anthropic


I lead the alignment team at Anthropic, where I’m working to reduce existential risks from AI systems. I led the team that developed Constitutional Classifiers, the first approach capable of robustly preventing most bad actors from obtaining harmful information from AI systems. I also helped develop Retrieval-Augmented Generation (RAG) and introduced Automated Red Teaming, both now widely used across major AI labs.

I received my PhD from NYU under Kyunghyun Cho and Douwe Kiela, funded by NSF and Open Philanthropy. I’ve previously spent time at DeepMind, Meta AI Research, University of Montreal, Uber, and Google. I was named one of Forbes’s 30 Under 30 in AI.

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