Missel of the 40 – This book offers a critical reading of the book « L’art d’être chef » (The Art of Being a Leader), written by Gaston Courtois, a French clergyman, and published in 1940. « L’art d’être chef » is a collection of 673 maxims and thoughts about being or becoming a good leader. Noting the absence of women, both in the subject and in the group of people it is designed for, I decided to confront this same text with forty portraits of women with an unusual destiny. 20 women portraits are related to the date of publication of the book. The other 20 appear in the form of inserts, as if they had been collected over time. Through these portraits, the book displays 24 centuries of women’s struggle to gain access to the same rights as men. Finally, it is in the form of a missal that I decided to share this patriarchal rhetoric on the art of being a leader and the unusual life and destiny of these women.