This introductory chapter reflects on current debates about the challenges faced by multicultural societies in coming to grips with the interrelated societal tasks of facilitating migrant settlement, nurturing cultural diversity and pursuing inclusive citizenship. In doing so, the chapter will explore the development and deployment of the concept of ‘multiculturalism’ from a comparative and historical point of view and will proceed to discuss its key assumptions, achievements and challenges. The chapter will also touch upon the key theoretical paradigms debated in this book and will attempt to synthesise conceptually how its three sections interconnect dialectically and empirically.