Christian radio is a growing sector; its North American presence, in terms of number of stations, has more than doubled in size in the last twenty years. Yet there is little coverage of this broadcasting format, particularly disinterested academic discourse. This study seeks to address this absence, and to provide a summary of the evolution, role and significance of Christian radio in US radio broadcasting. It attempts to define what we mean by Christian radio, and to examine the drivers of its recent growth. Finally, the article presents some reflections on the possible future of the format, and whether or not this growth represents an important trend in the radio industry.