Professor Gregory's areas of specialization are Byzantine history and classical archaeology. Director of The Ohio State University Excavations at Isthmia and Co-Director of the Eastern Korinthia Archaeological Survey, Professor Gregory's primary interest is the use of archaeological evidence for historical reconstruction. He is working on a "landscape approach" to the history of the Eastern Mediterranean area, especially in Late Antiquity and the Middle Ages. His publications include books and articles on the archaeology of Greece and the history of early Christianity. He teaches courses on classical archaeology and Byzantine History.