This week in New York City, the United Nations is holding its second global Water Conference -after a gap of 46 years. At the first meeting in 1977, climate change was not even on the agenda. Today, there is stark evidence that the world is warming and that greenhouse gases from fossil fuels are to blame 1,2 . At the same time, the global water cycle has been wrecked by decades of mismanagement and intensified by climate change. As a result, 1.5 billion to 2.5 billion people live in areas where water is scarce for at least part of the year 1 -and those numbers could double by 2050. Strategies for governing water and addressing climate change in tandem must be higher on the political agenda.This matters for three reasons. First, water is the primary medium through which people experience climate change. Three-quarters of all disasters are water-related 3 . In the past year alone, massive floods have affected at least two-thirds of Pakistan's districts; extreme drought has devastated the Horn of Africa; and Europe, the western United States, Australia and parts of Latin America have experienced both extremes. Many of these events have a clear climate-change fingerprint. Along coasts Managing water and climate in tandem would protect water resources, reduce disaster risks, lower greenhouse-gas emissions and assure equitable access.