This chapter explores when the government’s religious speech violates the EstablishmentClause, which commands that the government “shall make no law respecting an establishment of religion.” It examines how courts and commentators have identified at least three different approaches to this question. Under the noncoercion principle, we focus on the effects of the government’s religious, specifically asking whether it coerces listeners’ religious belief or practice. Under the nonendorsement principle, we ask whether the government’s speech endorses religion in ways that communicate a message of exclusion to nonadherents. Finally, under the neutrality principle, we turn to the government’s purposes, asking whether the government seeks to advance religion through its speech. The chapter then applies these approaches to a range of problems involving the government’s prayers, religious displays, and its statements that reflect religious animus. It closes by briefly considering when constitutional challenges to the government’s speech are justiciable—that is, when the federal courts have the constitutional power to decide them—a question to which later chapters will return.