The lichen flora of hazel woodland on the island of Eigg off the west coast of Scotland is described. One area is interpreted as representing ancient ‘climax’ woodland partly on account of its rich epiphytic lichen flora. At other sites various levels of exploitation have modified the lichen communities. Site comparison has enabled a number of species to be recognised which may be useful in the recognition of relict hazel woodland in other oceanic areas. The ecology of the indicator species is discussed. Pertusaria alpina Hepp ex Ahles is reported as new to the British Isles.