In What She Means, writer and curator Hilton Als provides an exploration of the visual corollary to Joan Didion's life and work, examining the impact she has had on admirers, detractors, and critics alike. The book is organized chronologically, highlighting Didion's fascination with both the West and East coasts that shaped her identity. As a Westerner living in New York, Didion offered a unique perspective on her native land.

The book features over 50 artists, including Brice Marden, Ed Ruscha, Betye Saar, and Vija Clemins, working across various mediums such as painting, photography, sculpture, video, and film. Additionally, three previously uncollected texts by Didion are included in the book, offering further insights into her thoughts and reflections on different aspects of life and society.