Book excerpt: This is the first ever comprehensive English-language survey of Zoroastrianism, one of the oldest living religions Evenly divided into five thematic sections beginning with an introduction to Zoroaster/Zarathustra and concluding with the intersections of Zoroastrianism and other religions Reflects the global nature of Zoroastrian studies with contributions from 34 international authorities from 10 countries Presents Zoroastrianism as a cluster of dynamic historical and contextualized phenomena, reflecting the current trend to move away from textual essentialism in the study of religion