Dear Diego is a testimonial work of fiction in the Latin American tradition of the novela testimonio (testimonial novel) developed by the Cuban author Miguel Barnet with his famous Biografía de un cimarrón (1966; The Autobiography of a Runaway Slave, 1966). The most important element in this kind of literature is the use of a “witness” to provide the writer with the basic monologue in which the character tells his or her story. In Dear Diego, the “witness” is the chapter dedicated to Quiela by Bertram Wolfe in his biography of Rivera. Poniatowska read Wolfe’s biography and from this material developed the story line of her novel; she thus created a work in which it is the written word itself that acts as the “witness” of the story. The basic monologue is derived not from an interview with Angelina Beloff herself but from research on Beloff done by Poniatowska. The final monologue presented by the narrator is the collection of letters. In this respect, the novel does not follow the testimonial fiction structure of the first voice telling the story. In Dear Diego, the letters to Diego Rivera from Angelina Beloff constitutes the narrative discourse.