Jean-Guillaume de Tocqueville devotes a significant part of his work to promoting the intellectual legacy of Alexis de Tocqueville, notably through the Tocqueville Foundation, which he founded and currently chairs. Through the organization of the Tocqueville Conversations, he fosters a transatlantic dialogue on democracy, human rights, and philanthropy.

Jean Guillaume is a lawyer and is a member of the Paris and New York Bars. He practiced in the M&A and the banking and finance sectors for a number of years. Since January 2025, he has served as Secretary General of the High legal committee of the Paris financial center.