The Art of Avaz and Mohammad Reza Shajarian: Foundations and Contexts, by Rob Simms and Amir Koushkani, examines the traditional art of singing classical Persian poetry, as represented by its greatest living exponent. Focusing on Shajarian's early career up to 1979, this in-depth study includes a panoramic view of the social and historical context of the twentieth-century tradition of avaz, along with a detailed presentation of Shajarian's musical toolkit for weaving together poetry and Iranian musical modes.