Every field of study develops key terms and concepts that establish the foundation for conversation. Terms in Interreligious Studies are still in flux. That should not be surprising since the field is relatively young—and since many aspects of religion itself are still debated in the academy, including ways it has “colonized” thinking about diverse traditions. Chapter 2 presents a range of terms and concepts, explaining how the book uses them. In the process, it illuminates some of the challenges in naming and navigating religious difference.