availability and its variations both in space and time which are always associated with a high degree of uncertainty. To summarize current views, it is fair to say that there are more clouds on the future of water availability for food production than on the ability to produce sufficient food in the future. This is particularly the case for irrigated agriculture, which will need additional water supply to meet the challenge of producing more in the coming decades (Molden, 2007). However, in many water-scarce areas, there is already a shortage of agricultural water and additional allocation at the expense of other users, notably the environment, would probably be unacceptable to society. The trade-offs that will be faced in the allocation of water to the different sectors will cause important conflicts in some regions that will be very difficult to resolve. Climate change (CC) will affect both future agricultural production and water availability. However, most modelling exercises and experimental evidence (Kimball et al., 2002; Ko et al., 2010) indicate that CC would have a neutral to a relatively modest positive effect on agricultural production processes globally, at least to 2050. Although there are many complex interactions (Leakey et al., 2009), one generalization that can be made from the studies conducted so far, is that the negative effects of the higher temperatures more or less balance the positive effects that the increase in CO2 concentration will have on the photosynthesis of C3 species. By contrast, the effects of CC on future water availability for agriculture are much more uncertain. There is already evidence of an ongoing intensification of the hydrologic cycle, as shown by changes in some key variables globally and regionally (Huntington, 2010). However, its impact on agricultural production is very difficult to predict as it depends on other variables such as the frequency, intensity or duration of extreme-weather events, for which the evidence for an increase due to CC is mixed and remains uncertain (Huntington, 2010). Nevertheless, when the socioeconomic trends are added to the biophysical evidence, all that can be said today from a scientific viewpoint is that, at the very least, CC adds another dimension of uncertainty to the challenge of dealing with climate variability in the path of meeting food demand by 2050