It has been estimated that more than 8090 of the world's scientists who have ever lived are still alive today. It would not be unreasonable to suggest that more than 95% of those who have ever used a mass spectrometer are not only alive but are still actively employed. Most have never had any formal training in the subject since, with a few notable exceptions, universities have only recently begun to offer courses in mass spectrometry. We have written this book for the student of modern mass spectro­ metry: it is for the novice who wished to know what the instruments can do and how the techniques can be applied. There are other books on the market which delve into the history of mass spectrometry and go deeply into the mathematical theory and instrumentation. There are yet more books which guide one through the art of interpreting spectra. We have deliberately avoided these topics so that the reader is confronted only with the basic principles and is allowed a taste of the applications. One of the best methods of deVeloping a useful textbook is to teach a course based upon its content. This is what we did. We met in Houston in 1976 to teach a course on "Perspectives in Mass Spectrometry" and to coordinate our writing. The authors of five of the chapters met again in St.