The authors wish to thank the World Bank for having made available the findings of the Sub-Saharan Water Harvesting Study on which parts of this publication are based. Photographs are by Will Critchley. Thanks are also due to Mr. D. Mazzei of FAO for his assistance with the illustrations for this manual. Finally, Ms. C.D. Smith Redfern of FAO deserves a special note of gratitude for typing, correcting and advising on layout and, in general, putting the whole paper together.