Ryan Holiday is a bestselling author, entrepreneur, and public speaker known for his modern interpretations of Stoic philosophy and its applications in daily life and professional environments. He began his career as a media strategist, notably working as the director of marketing for American Apparel. Holiday also founded Brass Check, a creative consulting firm that has worked with notable companies such as Google and Complex, as well as prominent authors like Tim Ferriss and Tony Robbins.

Holiday has written several influential books, including The Obstacle Is the Way, Ego Is the Enemy, and Stillness Is the Key, which together have sold millions of copies worldwide. His works are celebrated for their actionable wisdom and have been embraced by leaders in sports, business, and politics. He is also the creator of The Daily Stoic, a platform providing insights and resources about Stoicism, including a popular book by the same name.