This fourth collection by David Jacoby focuses on Western economic expansion the Eastern Mediterranean during the 11th-15th centuries. He is concerned to emphasize the interconnections linking the West, Byzantium and the Levant, and to examine normative sources for commercial activity (charters, etc.) against the background of actual practice, such as reflected in notarial documents. The articles deal with the evolution of urban centres, the trade in raw materials, and at the same time questions of technology transfer and the mobility of merchants and craftsmen. Particular attention is given to the silk trade: the author argues that demographic expansion in the Byzantine world, as in the West, stimulated economic growth, and demand for silk led to the emergence of a market-driven industry in Byzantium.