Book excerpt: Describes recent advances in ion chromatography and demonstrates how it is used to solve scientific and industrial problems. The basic principles of ion chromatography are explained, including gradient elution of ions and micromembrane suppressors. The various anion and cation exchange columns together with various detection methods and applications of ion chromatography in the environmental and life sciences and industry are reviewed. Over 100 chromatograms which illustrate parameters needed to perform analysis and data on gradient and mobile phase ion chromatography are included.