Huttar has published widely on Renaissance and 17-century literature and the works of C.S. Lewis, Charles Williams, and J.R.R. Tolkien. He edited or co-edited the books Imagination and the Spirit: Essays in Literature and the Christian Faith Presented to Clyde S. Kilby (1971), Word and Story in C.S. Lewis (1991), The Rhetoric of Vision: Essays on Charles Williams (1996) and Scandalous Truths: Essays by and about Susan Howatch (2005). Most recently, his scholarly work has included multiple journal articles and reviews; a chapter for the book The Inklings and King Arthur, edited by Sørina Higgins; and writing an in-progress book with the projected title New Bodies in Narnia and Elsewhere: C.S. Lewis and the Mythography of Metamorphosis.