Alexander’s research interests focus on the middle and late Byzantine period and may be divided into three areas: Byzantine diplomatics and institutional history; diplomacy, communication, and cross-cultural exchange between Byzantium and the Muslim world; Byzantine-Frankish contacts in the crusader states and the Eastern Mediterranean. He has published two monographs on the transmission of Byzantine letters and official documents in Arabic medieval sources and on Greek documents issued in the crusader kingdom of Cyprus. His scholarly articles address forms of communication and ritual aspects in Byzantine-Muslim relations, and institutional and social transformation in Frankish-held territories of Byzantium. He has collaborated in a major project of the Bavarian Academy of Sciences on summaries of Byzantine imperial charters and has co-edited collective volumes on diplomatics and ceremonies in the Eastern Mediterranean. More recently, he works on the perception of Byzantium, the papacy, and medieval western kingdoms in Muslim sources and Byzantine perceptions of the Seljuk Turks in Asia Minor.
