AHMET YUKLEYEN, while a student at Boston University in Boston, Massachusetts, received an award in June 2003 to aid research on Islamic organizations in Europe, under the supervision of Dr. Jenny B. White. Transnational Islamic organizations in western Europe do not simply transplant religious extremism from their countries of origin. Rather, they play an intermediary role, negotiating between the social and religious needs of Muslims and the socioeconomic, legal, and political context of Europe. The diverse forms of religiosity institutionalized by Turkish-Islamic organizations permited a comparative analysis of this intermediary role. Yukleyen looked at the internal dynamics-religious authority, primary field of activism, and boundary maintenance-of three such organizations: Milli Gorus, representing political Islamism; Suleymanli, a branch of the Naqshibandiyya Sufi order; and the Nur movement, a piety-oriented da'wa (missionary) movement. Religious authority involved individuals, positions, and actions that represented collective identity and preserved group cohesion by controlling and disciplining members and dropouts-that is, through boundary making. Each group's field of activism-politics, education, or religious instruction-promoted the type of knowledge embodied by the religious authorities and distributed through boundary making. Redefinitions of religious concepts such as hijrah, jihad, and neighborly relations created a Muslim sense of belonging to the European home. Overall, a comparative analysis of the internal dynamics of transnational Islamic organizations yielded a fuller understanding of their roles in the production and dissemination of Islamic knowledge and practice in western Europe.