ABSTRACTThe dormouse survey was initiated by the Mammal Society and ran from January 1975 to April 1979. The dormouse is very much a southern mammal in Britain with a reduced range compared to that found 100 years ago. There seems to have been a decline in population and possible reasons for this are discussed. The habitat favoured by dormice is considered; a thick secondary layer is very important with bramble forming a major component. Dormouse nests are most often found in bramble at an average height of just over a metre from the ground. Dormouse requirements, particularly for scrub, should be considered when areas for wildlife conservation are being managed.