Scale Issues in Hydrological Modeling is a collection of 27 papers presented at a workshop in Australia in 1993 and later published in two special issues of Hydrological Processes. It is one of the few books that addresses the scaling problem in hydrology: that is, how to transfer information from one scale to another and how to handle spatial heterogeneity. It gives us a flavor of the nature and extent of the scaling problems in hydrology, although no general answers are provided.