Cassidy undertook her PhD in the Department of English, University of Sydney, researching the poetics of Jennifer Rankin and Jennifer Maiden (qq.v.). She has been a member of the Red Room Company, Australia's only poetry company, and has worked for the company as a researcher. Cassidy edited an anthology of new work by writers featured at Sydney's 2005 'The Salon' debate nights, assisted by the Australia Council for the Arts. She has also worked as a casual tutor and librettist.
Certain Fathoms2012selected work poetry 'Bonny Cassidy's first book, Certain Fathoms, glimmers with precisely observed moments that make a strange place of the familiar. These poems speak not only to each other but to and of other writers: Eve Langley, John Berryman, JS Harry. Cassidy knits seemingly small phrases and events into glimpses of a vast, interconnected whole. There is a mapping-out here that is organic, not programmatic, preoccupied "with more-than-human subjects," the trains of phrase and acquaintance,/ unstopped chains of heat, return, death". Cool, yet engaged, Cassidy's poems swell with the movements people and things make, making them brightly and newly visible.' (Publisher's blurb)