Acknowledging in his preface that hydrology has been almost taken over by mathematical modeling, Mazor (emeritus, Weizmann Institute of Science, Rehovot, Israel) nevertheless makes the case for field observations and measurements. Filling this text with numerous case examples, he discusses observation-based research approaches to the study of the dynamic behavior of global water systems and the underlying variables affecting global water balance and supply, in particular the management of fossil groundwaters. Coverage includes groundwater exploitation and preservation, petroleum genesis and exploration, thermal water recreation and energy production, and nuclear waste repositories. The answers to exercises are in the back of the book.