This book has arisen from a series of lectures developed by Dr Gillan McMahon and delivered to students on the taught postgraduate module on instrumentation at Dublin City University. Gillian was previously herself a student in DCU and since graduating, she has developed her analytical background initially in industry in the pharmachem arena, and more recently, as a very successful academic teacher and researcher. She gained a wealth of experience over a broad range of analytical techniques in the pharmachem industry, working with the Geotest Chemical Company (USA), Newport Pharmaceuticals (Ireland), Bristol-Myers Squibb (Ireland) and Zeneca Pharmaceuticals (UK). This experience applied not just to the use of techniques.