This volume collects the communications from the 10th International Symposium of Byzantine Sigillography (Ioannina, 1st-3rd October 2009). The scientific focus of the Symposium was the combination and the common ground between Sigillography and Archaeology. Experts from around the world and many archaeologists with fascinating sigillographical findings responded to this call. The papers have a synthetic nature dealing with the byzantine lead seals as a historical source and their significance for the history of the byzantine civil and military administration, the relations with the West, the history of Art and the byzantine prosopography. Some papers also present new unpublished findings from excavations in Turkey and Greece and from the Collection in the Ermitage Museum (St. Petersburg), which is the second biggest collection of byzantine seals all over the world.