This paper introduces the papers in this special issue and uses them as evidence through which to examine four questions. First: are we witnessing a widespread (re)turn to big infrastructure projects for water management? The evidence suggests that large-scale infrastructure development has remained largely unswayed by the 'ecological turn', or the promotion of demand management or 'soft path' thinking, despite a drop in investments observed at the turn of the 20th century. Second: do these new projects have different justifications from those of the past? The papers in this issue provide evidence that the need to justify capital-intensive infrastructure in the face of commitments to sustainability, while borrowing from the conventional grammar of project justifications, has generated a few innovative tropes and rhetorical devices. Third: what does a (re)turn (or enduring commitment) to big infrastructure tells us about the governance and wider politics of large-scale infrastructure problems?

Some of the traditional interest groups are well represented in the stories told here - the corporations that demand water or compete to build pipes and dams; the large-scale irrigators that rely on water to expand their production; the engineers and consultants who seek money, prestige, career advancement or even satisfaction from 'controlling' nature; the politicians who can extract 'rents' from all this activity. Even so, the history of each particular project involves many contingencies - of the society's history, of previous rounds of infrastructure and of capital availability. Fourth: have there been changes in the scale at which water is managed within countries? In general, it seems there has been an increase in the scale of projects, generally involving a shift in power away from regional and up to multi-regional agencies of governance, such as the central state. Sometimes these shifts in scale and power have no effect on the salience of local voices - because in the past they were never heard or generally suppressed anyway. Sometimes the shifts in power and scale have been accompanied by increasing suppression of local voices of opposition. In one case - South Africa - the change in scale has seen a stand-offbetween representatives of new voices and the infrastructure-focussed engineering elite.