📗 The book shows principles and applications of the most distributed technique used for water analysis. The central laboratory of Greater Cairo Drinking Water Company (GCWC) uses this important technique and applies the analytical methods recorded in the standard methods for water and wastewater examination. This laboratory represents nucleus and origin of many reference laboratories of water analysis in Egypt. Wael Mahmoud and his team of the researchers modified the scientific cooperation between the central laboratory of GCWC and the national research centre. Wael and his team used the chromatographic techniques in the central laboratory to make their ideas and researches in field of the water examination. They added new concepts in the technical uses of the chromatographic techniques and without scientific experience of this team, the central laboratory still do the routine and traditional analytical work without any improvement. The book confirms the concept which explains that it is impossible for the traditional technical work to progress without science.