Recent developments clearly indicate that speciation studies in biological and environmental matrices are much more important than the total element determination due to the tremendous difference in bioavailability and toxicity of various chemical forms of a particular element. Different separation-detection techniques and hyphenated systems--each with its own advantages and disadvantages with respect to precision, sensitivity and detection limit--have been developed for the identification and quantification of the species present in systems at ultra-trace levels. This book aims to evaluate the speciation analysis in depth and present a comprehensive review of state-of-the-art analytical approaches used for the speciation of elements in environmental samples.