Excavations on two of the major mounds at Harappa have revealed traces of an early settlement, a transitional phase of development, and several phases of full urban and post-urban occupation.

"The theme of this volume has forced us to consider and grapple with what activities occur at night and how that can be applicable to the archaeological record of the Indus civilization. In doing so we have focused on water and sewage system maintenance, a traditional nighttime activity of the modern world, to demonstrate how the common spaces and activities of maintenance would have constructed a shared sense of belonging for participants and/or imposed shared identities upon them by outside viewers," write the authors.