Content Separating and purifying the desired product is an important part of any bio-project. This processing 'downstream' from the fermenter is both difficult and expensive. Our book intro-duces all the common techniques, starting in the lab and ending in the plant. We have written it for undergraduates in process engineering (biotechnological, mechanical or chemical) and graduate microbiologists doing a minor on the technology that is required to scale up their experiments to a commercial scale. The text is also suitable for courses in industry. The Authors J.A. (Hans) Wesselingh studied engineering physics and worked for the Shell Group for many years. His last job there was as leader of a group developing large scale reactors and separation equipment for oil, gas, chemicals and biotechnology. He later worked as professor on separation processes and product development at Delft University of Technology, the University of Groningen and the Technical University of Denmark. He has been a consultant to many Dutch process industries. John Krijgsman is a mechanical engineer by education and a biochemical engineer by experience. He has worked in the food industry and for many years with the Dutch biotechnology company Gist-Brocades (now part of DSM). He has been a major contributor to large biotechnological projects. John has taught downstream processing to students at the Delft and Eindhoven Universities of Technology. He is owner of Biogonaal, a consultancy for food and biotechnology.