Counting Religion in Britain, 1970-2020, the fourth volume in the author's chronological history of British secularization, sheds significant new light on the nature, scale, and timing of religious change in Britain during the past half-century, with particular reference to quantitative sources. Adopting a key performance indicators approach, twenty-one facets of personal religious belonging, behaving, and believing are examined, offering a much wider range of lenses through which the health of religion can be viewed and appraised than most contemporary scholarship. Summative analysis of these indicators, by means of a secularization dashboard, leads to a reaffirmation of the validity of secularization (in its descriptive sense) as the dominant narrative and direction of travel since 1970, while acknowledging that it is an incomplete process and without endorsing all aspects of the paradigmatic expression of secularization as a by-product of modernization.