Three questions command even greater attention today, as over forty countries, including many Muslim-majority states, unite against Daesh (the so-called ‘Islamic State'): How do Muslims relate to the Muslim ‘other'? How do Muslims relate to the religious ‘other'? What role can Muslim religious education play in fostering peace? Islam and Muslim education are suspected of promoting intolerance. This thesis investigates a group of Shia Ismaili Muslim trainee-teachers' attitudes to plurality in their religious education programme. The Secondary Teacher Education Programme (STEP) is a two-year postgraduate course of the Ismaili Muslim community to train religious education teachers. STEP, a novel development in Muslim education, experiments with an innovative pedagogical approach to plurality. The research spanning over three years involved in-depth interviews, focus group, observations and textual analysis. 21 trainee-teachers from 13 different countries participated in the study. Alan Race's (1983) typology ‘inclusivismexclusivism- pluralism' serves as a key theoretical lens through which to examine attitudes to religious others. The thesis argues that a ‘rooted religious pluralisation' is taking place in the Ismaili community facilitating the emergence of the ‘tradition' of pluralism in the community. The study shows that initially, the participants were inclusive of other religious communities and worldviews on ‘theological', ‘humanistic' and ‘instrumental' grounds, but were selective about how they embraced it. Many of them believed that their religious perspective exceptionally equipped them over their religious ‘other'. Gradually, STEP's ‘civilizational, normative and humanistic' approach cultivated an ‘academically informed pluralism' in most trainee-teachers. It strengthened their Ismaili Muslim identity on the one hand and generated an appreciation for diversity on the other. The individuals developed not only greater socio-cultural and historical awareness of religion, but also their ability to make a space for faith academically. It cultivated in the participants a degree of ‘inter-tradition competence' and ‘intra-Islam competence'. The individuals were not ‘pluralist angels', but they discursively participated in pluralism. The present study makes three key contributions. Firstly, this is the first study to propose the thesis of ‘rooted religious pluralisation'. It identifies the key features and tendencies inherent in a religious community's engagement with diversity through a five-dimensional working framework. Moreover, as a study of the socio-cultural process of ‘intra-faith pluralisation' in Muslim religious education setting, it is unique. It is about making sense of the everyday experiences of the Muslims who encounter diversity within their own faith. The thesis identifies various stages involved in the process of developing intra-faith competence and provides tools and vocabulary to discuss them meaningfully. Moreover, the study suggests the possibility of a Muslim education that can play a vital role in combating extremism and sectarianism. Current scholarship does not sufficiently take account of new and thought-provoking pedagogical developments in Muslim education. There is a dearth of studies on Muslim faith communities' efforts to build ‘intra-Islam competency' in their followers through faith-based education. The literature is also silent about how Ismaili Muslims handle differences among themselves regarding matters of faith, how they view differences within Islam and relate to wider religious plurality. Thus, the study contributes to a niche in the existing literature on religious pluralism.