The ecosystem approach may seem a senseless luxury for water managers in the developing world who regularly ‘face the facts’ that 30,000 children die each year because of inadequate water supply or sanitation and half of the world’s hospital beds are occupied by patients with water-related diseases. The UN’s International Drinking Water Supply and Sanitation Decade (1981-90) was the first major international assault on the appalling statistics of inadequate or polluted water supplies for human use (Agarwal et al., 1980). At the close of the Decade, 700 million extra people had been supplied with clean water but nearly 2 billion people remained in danger – a vanishing perspective.