To understand the relevant and signifijicant diffferences between imams of the West, this chapter suggests a typology of imams according to variations of institutional authority – that is, the signifijicant dimensions of institutionally embedded authority available in the West – and what has been called epistemic authority, which emphasizes the primacy of knowledge-based authority in Islam. Focussing specifijically on Islamic authority and providing relevant examples of imams that embody authority, the typology expresses the cross tabulation between the diverse institutional frameworks in the West and Islamic knowledge personified.This relationship between institutional authority and epistemic authority, its explanatory power and the actual imams, who exemplify them, is a telling indicator of the directions and future challenges of Islam in Europe.