Irene Perry took up the study of mosses and liverworts after being struck by their beauty and variety at a nature reserve managed by the Exmoor Natural History Society. She became the Society's Bryophyte Recorder in 1993. Together with a small group of enthusiasts she has visited every area of Exmoor, gathering the records which form the basis of this Atlas. Nearly 400 species have been found and around 12,000 items computerised. This is the first published work on Exmoor Bryophytes and as such must take an important place in natural history recording on Exmoor.