The diffusive gradients in thin-films (DGT) technique is a means of measuring the concentration and speciation of metals in natural waters. Edited by one of the pioneers of the technique, this unique volume provides a complete and authoritative guide to the theory and applications of DGT. The book includes explanations of the fundamental principles of DGT, accessible to readers with a modest background in chemistry, as well as more advanced chapters that provide a thorough treatment of the physical and chemical dynamics of this technique and evaluate how well it mimics the biological uptake process. Chapters on natural waters, soils and sediments illustrate the applications of DGT, and detailed instructions are included on how to use DGT in practice. Combining the fundamentals of DGT with more advanced principles, this is an indispensable text for students, researchers and professional scientists interested in the chemistry of natural waters, soils and sediments.