Prospects of an “Islamic Reformation” and a “Muslim Luther” have been much discussed in recent years. This “Reformation” rhetoric, however, displays little consistency, encompassing moderate, liberalizing trends as well as their putative opposite, Islamist “fundamentalism.” After briefly surveying the history of “Islamic Reformation” rhetoric, my paper argues for a four-part typology to account for most recent instances of such rhetoric. I show that few who employ the terminology of an “Islamic Reformation” (IR) consider the details of its implicit analogy to the Protestant Reformation, but rather seek to add emotional weight to various prescriptive agendas. Still, some examples demonstrate the potential power of the analogy to clarify important aspects of religious, social, and political change in the modern Islamic world. I explore a broad range of mostly English-language sources, academic and otherwise, to illuminate one specific element of contemporary Western views of Islam and Muslims. I first document several 19th-century assertions that early Islam was subject to a “Reformation.” One 1883 source attributes an “Eastern Reformation” to the work of al-Ash`ari (d. 324/935) while deriding Ash`ari’s supposedly anti-rationalist stance. Muhammad `Abduh (d. 1905) argued that the return to Europe of Christian Crusaders impressed with the “reasonableness” of Islam sparked the Protestant Reformation itself. My typology of contemporary rhetoric begins with sources treating the IR as a liberalizing corrective to perceived illiberal, “fundamentalist” tendencies. Primarily a post 9/11 phenomenon, this type includes Abdullahi an-Na’im’s sophisticated legal reform agenda as well as Irshad Maniji’s and Salman Rusdhie’s calls for a “Reformation” as antidote to “jihadist,” intolerant Islam. My second type is a direct rejection of the first and argues that the IR should be understood instead as “fundamentalist” Islam itself. Samuel Huntington, Fareed Zakaria, and Denesh D’Souza decry the atavistic violence and internecine strife of the IR. Our third type holds that a liberalizing IR is not a cure for but a mortal threat to Islam; this position produces the strange bedfellows of Sayyid Qutb (d. 1966) and Stanley Fish. Those of my fourth type largely ignore these debates over the “IR as liberalization” to explore the specific potential of the analogy (perhaps in its negation) to illuminate modern Islamic history. Dale Eickelman and Felicitas Opwis demonstrate the value of carefully comparing Muslim and Christian histories of reform. I close by asking what makes the “Reformation” analogy so enticing and generalizing about what can be gained or lost in employing it.