The key task for Christian public theology is to determine the most effective way in which theological insights can contribute to the public good within any given polity and beyond. In the past the assumption has been that this task is undertaken in a secular political environment. After examining different ways in which such an environment might be understood, this article examines the approaches of Stanley Hauerwas, Rowan Williams and Oliver O’Donovan to Christian political engagement. These approaches are characterized as separatist, pluralist and sympathetic to Christendom. Subsequently there is a shift in focus to consider how relevant these approaches are to the emerging post-secular and pluralist environment in the western world. While there is a range of approaches as to how to pursue the public good in this context, I argue that Hauerwas, Williams and O’Donovan remain relevant, contributing to the task of public theology in various ways.