This paper traces the phenomenon of polis desertion, exploring both its causes and its impact on the social and political landscape. It is argued that while the Greek poleis were highly vulnerable to ecologically and socially induced stress and catastrophe, they were at the same time remarkably resilient in a way that their individual inhabitants could not be. It is argued that this social resilience was a product of relations with other communities which served as a kind of buffer against risk; it is thus the communal response to stress and catastrophe that enables social resilience. A variety of relations between communities contributed to social resilience, including kinship, sympoliteia, and isopoliteia, but it is argued that the koinon was the most effective social structure in achieving this end, by institutionalizing economic and political relations between communities that allowed for diversification and redistribution of both populations and resources. In writing the history of abandonment in the Classical and Hellenistic poleis, evidence is drawn from literary and epigraphic sources as well as intensive and extensive survey, excavation and studies of landscape change in antiquity.