Social science analysis of diversity, and religious diversity in particular, has long struggled to move beyond simple binaries of religious-secular, religious-spiritual, traditional-modern, global north-global south, and so on. Twenty-first century realities test existing terms and find them wanting. While concepts such as the postsecular, multiple modernities, multiple secularities, and non-religion point to new lines of analysis, each still refers to binary and thereby limiting terms. This article reviews research on religious diversity, delineating some of the major challenges posed. Building on useful frameworks of superdiversity, multiple pluralities, and religious complexity, we argue that the more widely encompassing concept of worldview complexity might represent a better way forward. It has the advantage of acknowledging the intersecting diversity of diversities in multiple, differing contexts, and abiding similarities in what is occurring ‘beneath religion’.