Describes the theory, apparatus, performance and usage of modern methods for trace element determination, atomic absorption, emission, fluorescence and mass spectroscopies, x-ray techniques and activation analysis. Attention is given to sample preparation, current calibration procedures and to methods for trace element speciation. Contains in-depth information on relatively new techniques such as ICP-MS and PIXE. All methods are illustrated with authentic examples from the ever-expanding fields of environmental and biological analysis of high purity materials.