Isotope hydrology is a field of hydrology which is concerned with the utilization of isotope dating to estimate the age and origins of water. It also studies the movement of water within the hydrologic cycle. Water consists of water molecules carrying unique fingerprints located in part on different proportions of oxygen and hydrogen isotopes. Isotope hydrology helps in creating an elaborated picture of earth's water resources. It is primarily involved in using stable isotopes to determine the age of ice or snow. Its techniques are also used for conserving water supplies, controlling pollution and mapping aquifers. This book outlines the processes and applications of isotope hydrology in detail. It will also provide interesting topics for research which interested readers can take up. Those in search of information to further their knowledge will be greatly assisted by this book.