Small tanks are associated with villages or human settlements. However, these tanks did not merely serve man’s needs to produce food in the immediate sense. Most of the tanks were built to protect the ground water, to act as silt traps for the bigger tanks, and to provide water for non-human life. As the papers in this publication show, many of the people have contributed to the maintenance of ground water levels of a zone that receives its rainfall within four months of a year. These papers explore the uses of the tanks, the dependency levels among villages on tank water, and the role of tank irrigation in Sri Lanka.