In this chapter, a corpus of letters extracted from Imami Shiʿi hadith reports is analyzed to provide an overview of the system of imamic epistolary communications between imam and community members in Imami Shiʿism of the ninth century CE. The mechanisms by which letters reached the community are analyzed, including the mediation of agents (wakīl) of the imams. In particular, circular letters are looked at as illustrative of the ways in which the imam attempted to reach sections of his community beyond specific individuals, and the ways that these illuminate the distinctive aspects of Shiʿi community organization. The letters analyzed here indicate the existence of a relatively complex organizational web in the Imami Shiʿi community, whose efficacy was greatly dependent upon the trustworthiness of the individuals representing the claims of the imam to the constituencies in which they were embedded.