Bispira volutacornis, a sabellid polychaete, is an epibenthic filterfeeder. Its conspicuous appearance makes it a notable member of the marine hardbottom communities around Ireland and Britain. Bispira volutacornis is credited with having a 'key role' in certain hard bottom communities. The literature on Bispira volutacornis prior to this study was restricted almost exclusively to faunal records and descriptions of the external morphology, with knowledge of its biology and ecology being very fragmentary and this paucity of information prompted the current study. This study investigates different aspects of its biology and ecology in Lettercallow Bay, on the West Coast of Ireland, including: Examining the structure and functioning of the branchial crown; Investigating aspects of tube construction and role; Monitoring the reproductive cycle; and investigating the association with Gastrodelphys clausii. The result is a highly illustrated book which provides an insight into the world of featherduster worms and thus is of interest to both the general naturalist and those looking to gain further specialised knowledge.