By the time Christianity reached Iceland, saints’ lives were already a vast and enormously popular genre of literature well-established across the medieval Christian world. This chapter discusses how Icelandic writers engaged with this genre, concentrating especially on translated saints’ lives in Old Norse. While rooted in and responding to the particular conditions of Icelandic society, these vernacular adaptations and engagements with Latin Christian culture also transported the readers and writers of Old Norse-Icelandic literature far beyond their immediate environs. Beginning with the earliest examples of saints’ lives from the twelfth century, this chapter outlines how the genre developed over time from relative simplicity to a more complex and rhetorically accomplished approach. It describes how saints’ lives intersected with other forms of literature being written in medieval Iceland, including romance and the family sagas, and addresses categories of saint’s life which have received less critical attention: the Marian corpus, the lives of virgin martyrs and Low German translations into Old Norse-Icelandic.