This book shows how the change of water paradigm has become urgent, and provides evidence for new policies that expand water balance to green and virtual water. The issue of water security concerns drinking water supply but also food safety, linked to agricultural policy. Both rain-fed and irrigated agriculture play complementary roles in food security, and the water issue implies a holistic view of water resources. This view constitutes the book's backstory. The reader will find original ideas that can be applied everywhere because the example of Tunisia is typically a basis to illustrate a universally prevalent situation. The book deals with other important issues: desalination, wastewater recycling, water quality, groundwater overdraft, water savings, governance, knowledge valuing, education, information: upgrading the whole water systems for the future implies emancipation of the whole society.

This report contains essays by more than 50 experts in environmental and water resource issues who describe their visions of the field in 2050 and the steps necessary to make those visions a reality.

With a rapidly expanding economy many changes are taking place in India today. The business-as-usual (BAU) scenario, which assumes the continuation of current trends of key water demand drivers, will meet the future food demand. However, it leads to a severe regional water crisis by 2050, where many river basins will reach closure, will be physically water-scarce and will have regions with severely overexploited groundwater resources. While the alternative scenarios of water demand show both optimistic and pessimistic water futures, the scenario with additional productivity growth is the most optimistic, with significant scope for reducing future water demand.