Justin Leidwanger's research and fieldwork focus primarily on the role of economic networks in ancient Mediterranean life. These interests lead him to spend as much time in, as around, the Mediterranean's waters, where his fieldwork explores the shipwrecks, ports, and ceramics that provide primary archaeological evidence for mechanisms of communication and exchange spanning the Hellenistic era through Late Antiquity. In 2012, he initiated the Marzamemi Maritime Heritage Project, which combines archaeology with heritage and tourism development in southeast Sicily. Since 2013, a major focus has been on excavation, management, reconstruction, and research related to the famous 6th-c. Marzamemi “church wreck”, which sank while carrying a massive cargo that included prefabricated architectural and decorative elements. From 2011 to 2015, he co-directed annual multidisciplinary maritime landscape investigations in the Archaic through late Roman harbors of Burgaz, off the Datça peninsula in southwest Turkey, with Elizabeth S. Greene (Brock University) and Numan Tuna (Middle East Technical University). Prior to this, he directed annual surveys off the coast of southern Cyprus (2003-2009). As a Fellow of the Penn Cultural Heritage Center, he has been involved in issues of ethical stewardship, diverse public engagement, and innovative strategies for incorporating underwater cultural heritage into economic and coastal development. He teaches courses and advises students on topics in Roman archaeology, trade and the ancient economy, Mediterranean seafaring, ceramic production and exchange, networks and connectivity, Greco-Roman architecture and engineering, and archaeological ethics. His lab at the Archaeology Center serves as a research base for field projects as well as a center for digital modeling (structured light scanning, photogrammetry, GIS, network analysis) and pottery analysis (petrography and pXRF).