In Cambridgeshire's Mosses and Liverworts, Chris Preston and Mark Hill describe the current bryophyte flora of the vice-county, based on a survey undertaken by local bryologists between 2000 and 2018. They analyse changes in its bryoflora, drawing on a rich corpus of earlier records, together with data from many specimens in the Cambridge University Herbarium. No other county has the same continuity of recording, which results from meticulous record-keeping by Dr Harold Whitehouse during the period 1950–1999. The initial chapters outline the geography of Cambridgeshire, describe the historic patterns of recording and analyse change in the major bryophyte habitats. These chapters are followed by detailed accounts of the 341 species recorded from the county since 1660. A picture emerges of a dynamic flora, with some species in decline, others increasing and a surprising number of temporary colonists.