He is a university lecturer, the founding editor of Blackwater Publishing and the now defunct New Binary Press, and the writer of several academics and creative books.
[20] O'Sullivan has also claimed that many Irish academics are working class,[21] that the humanities have a reproducibility problem,[22] and he has also publicly criticised students for anti-social behaviour.
[23] He has written several features and opinion pieces on more general social and political matters for periodicals in Ireland and internationally, including The Guardian, the LA Review of Books, and The Irish Times.
[27] O'Sullivan has been vocal on the economic realities facing independent publishing houses, as well as an advocate of the role they play in the development of literary communities.
He has called for "improved transparency" and "the removal of commercial influences" from literary competitions, arguing that "small publishers can't take risks on large entry fees if there is any doubt in their mind over how decisions are being made".
[35][36] Reviewing Courting Katie, Dedalus poet Matthew Geden describes O'Sullivan as a "vibrant voice" that offers "timely reminders to look closer at the world around us".
[37] Writing in Poetry Ireland Review, Jessica Traynor likens O'Sullivan to a "latter-day Kavanagh" who "breathes life into deserted streets and grey city corners".