Drawing on policy scholarship on four campuses, this panel will explore issues that lie at the intersection of environmental and development policy. Three of the papers deal with one pressing development challenge: providing access to safe water supply and adequate sanitation. Current estimates from the UN and the WHO's Joint Monitoring Project are that 780 million people do not have access to improved water supply and 2.5 billion lack access to adequate sanitation. Two of these papers explore this problem from a household-level perspective. The first (Cook et al) explores the time savings benefits associated with bringing water points closer to homes in rural Ethiopia, finding that women use saved water-collection time for food preparation, other household chores and socializing. The second (Jeuland et al) finds that households in rural Cambodia are willing to pay more for higher water quality, but that their perception of the quality of their own drinking water is uncorrelated with its actual quality. The third paper (Allaire et al) looks at the water and sanitation challenge from a country-level perspective in sub-Saharan Africa (SSA). The authors estimate the total economic gains foregone in SSA from not having adequate water and sanitation services, finding that the gap between actual and potential benefits is similar in both "emerging" and oil-exporting economies. They also explore what will need to happen to accelerate a downturn in the 'peak' of unrealized economic gains, finding that economic growth does not appear to be sufficient. The fourth paper (Damon et al) complements these more sector-specific papers with a broad perspective on "grandfathering" in environmental policy, synthesizing legal, economic and political science perspectives on its application. The paper also explores, analytically and empirically, the dynamic incentives created by grandfathering, with a particular focus on common property resource management contexts (often important in developing country contexts) and long-term international agreements.