The global water and sanitation community is currently wrestling with the policy implications of two important realizations. The first is that it is quite possible for cities to actually run out of water-for the piped network to run dry. The second is that in many locations, basic water and sanitation interventions do not result in the large public health improvements that many water and sanitation professionals had hoped. As water and sanitation professionals work out the implications of these two realizations on policy and planning for water and sanitation improvements in the Global South, they will require an in-depth knowledge of local housing, water, and sanitation conditions, as well as a nuanced understanding of how households prioritize improvements in housing, water, and sanitation. The chapters in this book about Kathmandu illustrate the types of analyses of local conditions that are needed. Kathmandu holds many lessons for the global community about households' responses to water scarcity and the management of water and sanitation services in periods of rapid urbanization and climate change. In Focus - a book series that showcases the latest accomplishments in water research. Each book focuses on a specialist area with papers from top experts in the field. It aims to be a vehicle for in-depth understanding and inspire further conversations in the sector.