We have much new evidence from the excavation of ports and shipwrecks around the Indian Ocean. This new evidence can be studied against the background of anthropological and historical knowledge of ships and maritime communities. By 2500 BC, regular maritime contacts involving at least three different traditions of shipbuilding and sailing, were well-established in several areas of the systems of seas that extend from East and Southeast Asia to the Red Sea, the Arabian Sea, and the Persian Gulf. After 300 BC these local systems were stitched together, linking the emerging empires of East Asia, South and Southeast Asia, and the Middle East and the Mediterranean into a vast network. The speaker presents a personal oveview of recent research from Egypt to Oman to Thailand and back to Madagascar.