S. T. Joshi is the author of such critical studies as The Weird Tale (Univ. of Texas Press, 1990), H. P. Lovecraft: The Decline of the West (Starmont House, 1990), The Modern Weird Tale (McFarland, 2001), and Unutterable Horror: A History of Supernatural Fiction (PS Publishing, 2012), which won the World Fantasy Award. He has edited a corrected edition of H. P. Lovecraft’s fiction (Collected Fiction: A Variorum Edition [Hippocampus Press, 2014]) as well as The Ancient Track: Complete Poetical Works (Night Shade Books, 2001; rev. ed. Hippocampus Press, 2013) and Collected Essays (Hippocampus Press, 2004–06; 5 vols.). He has prepared three annotated editions of Lovecraft’s tales for Penguin (1999–2004). His exhaustive biography, H. P. Lovecraft: A Life (Necronomicon Press, 1996), won the British Fantasy Award and the Bram Stoker Award; a revised and expanded edition has appeared as I Am Providence: The Life and Times of H. P. Lovecraft (Hippocampus Press, 2010).
Joshi has done scholarly work on other authors of supernatural fiction. He is the author of a bibliography (Scarecrow Press, 1993) and critical study of Lord Dunsany (Lord Dunsany: Master of the Anglo-Irish Imagination [Greenwood Press, 1995]), and a critical study of Ramsey Campbell (Ramsey Campbell and Modern Horror Fiction [Liverpool Univ. Press, 2001]). He has prepared editions of the work of Arthur Machen, Algernon Blackwood, Lord Dunsany, M. R. James, Ambrose Bierce, and other writers. He is the co-editor (with Stefan Dziemianowicz) of Supernatural Literature of the World: An Encyclopedia (Greenwood Press, 2005).
Joshi has edited such anthologies as American Supernatural Tales (Penguin, 2007), the Black Wings series (PS Publishing, 2010f.), Searchers After Horror (Fedogan & Bremer, 2014), A Mountain Walked: Great Tales of the Cthulhu Mythos (Centipede Press, 2014), and The Madness of Cthulhu (Titan Books, 2014–15).