Ranked in 1 Practice Areas
3

Band 3

About

Provided by William Long

UK

Practice Areas

WILLIAM LONG is global co-chair of Sidley’s highly ranked Privacy and Cybersecurity practice and heads the EU Data Protection group. He is also a member of the firm’s top-ranked Crisis Management and Strategic Response team, and he serves on the Steering Committee of the firm’s AI Working Group. William advises international clients on a wide variety of AI, GDPR, cyber incident, data protection, privacy, information security, social media, e-commerce, and other regulatory matters.

William has been a member of the European Advisory Board of the International Association of Privacy Professionals (IAPP) and on the DataGuidance panel of data protection lawyers. He also founded and assists with dplegal (“data privacy” legal), a networking group of in-house lawyers in life sciences companies examining international data protection issues.

Publications

William is also the author of a book on the EU General Data Protection Regulation and a contributor to a number of books on data protection, including leading legal textbooks published by BNA in the area of privacy, cloud computing and the use of health data. William has been interviewed widely for his thought leadership, including in such leading publications as the international New York Times, Financial Times and The Guardian and writes for a number of publications, including Thomson Reuters, Law360, and Global Data Review.

Chambers Review

Provided by Chambers

UK

Data Protection & Information Law - UK-wide

3
Band 3
Individual Editorial

William Long is the global co-chair of Sidley Austin's privacy and cybersecurity practice and heads the EU data protection group. He is a respected data protection and cybersecurity practitioner, well versed in compliance, processing, transfers and breaches.

Contributions

Latest contributions provided by William Long

Global Practice Guide
William Long
Eleanor Dodding
Anila Rayani
Francesca Blythe
Authored by
William Long, Eleanor Dodding, Anila Rayani, Francesca Blythe
Article • Feb 2025
Global Practice Guide
William Long
Francesca Blythe
Anila Rayani
Eleanor Dodding
Authored by
William Long, Francesca Blythe, Anila Rayani, Eleanor Dodding
Article • Feb 2025

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