This volume addresses the history and heritage of the ‘Macassan’ ishers who made the long and sometimes dangerous maritime journey from the port town of Makassar in southern Sulawesi to the coastline of Arnhem Land and the Kimberley, northern Australia, from before European settlement in Australia until the early twentieth century. The essays of this collection present an interdisciplinary perspective on the maritime journeys of the Macassans, as well as their encounters with Aboriginal communities in the north and the ongoing impact this exchange has had on Aboriginal languages, societies and cultures. The primary reason for the Macassan visits to the northern Australian waters each year was the collection of trepang (teripang in Indonesian), edible holothurians also known as sea cucumbers, bêche-de-mer or sea slugs. This volume addresses various aspects of the historical development and impact of the trepang trade as well as the enduring encounters between the Macassans and the Indigenous communities of northern Australia. Contemporary heritage iterations and reappropriations are also examined, including heritage listing possibilities, present-day trepang isheries and Australia–Indonesia bilateral marine cooperation and management.