This chapter examines the institutionalisation of Islam in the West with a focus on religious, legal, and educational institutions. Islamic institutions tend to represent the public interface of Islam with the state and society and as such their nature, orientation, and activities are a reflection of the faith in society. The chapter traces the evolution of this institutionalisation beginning with the provision of services to enable Muslims to fulfil religious requirements such as the right to build mosques and recognition of Muslim marriage and burial rites to those that cater to a more Islamist agenda of institutionalizing shariah through Muslim Arbitration Tribunals, sharia councils and courts as well as concessions for the incorporation of aspects of Islamist ideology into existing institutions under the guise of religion. It highlights that in many cases what is attempted to be institutionalised by Muslims is not religion per se but Islamist ideology. The chapter offers a cautionary note that supporting certain institutions in the name of equal citizenship, non-discrimination, and freedom of religion may in some cases be contributing to outcomes that undermine these values and principles.