Trade was extensive and apparently well-regulated, providing imported raw materials for use at internal production centres, distributing finished goods throughout the region, and arguably culminating in the establishment of Harappan “colonies” in both Mesopotamia and Badakhshan.

The remarkable uniformity of weights and measures throughout the Indus lands, as well as the development of such presumably civic works as the great granaries, implies a strong degree of political and administrative control over a wide area.