This book is based on the contributions to the IFAC-Workshop "Mass Spectro- metry in Biotechnological Process Analysis and Control" held in Graz, Austria from 23 to 24 October 1986. The idea to organize this workshop and further to prepare these proceedings was stimulated by the following facts. Biotechnological processes urgently need better on-line instrumentation. Mass spectrometry (MS) offers a great potential to especially analyse gases and volatile compounds. It is, however, considered that this potential by far is not exhausted. The main reason for this is that MS often still is...