More than one and a half decades have passed since the last book was published describing developments in the analytical chemistry of synthetic colorants. In the intervening period, the scope and technical capabilities of instrumentation for analysing dyes and pigments has significantly expanded. It is now possible to rapidly resolve a number of problems whose solutions were previously either unattainable or very difficult to achieve. For instance, the unambiguous assignment of all the signals in the proton NMR spectrum of a trisazo direct dye, and the confirmation of the molecular weight of involatile, and, in particular, sulphonated dyes, without derivatisation, are now routine analytical techniques in many laboratories today. In addition, it is now possible to record the NMR spectrum of a dye molecule on less than 1 mg of material, and we are no longer limited to solution spectra, since solid samples can now be routinely analysed in NMR experiments. Whilst not attempting to be all encompassing, this volume is intended to bridge the gap between what was covered in the earlier work edited by Professor Venkataraman and the developments which have since ensued in some key areas. It provides important updates in X-ray crystallography, proton NMR, IR spectroscopy and mass spectrometry, and additionally covers topics such as ESR, micro spectrophotometry and emission spectroscopy.