This book introduces the principles and concepts of chemical and biochemical sensors for analyzing medical as well as biological samples. For applications like analyzing or monitoring gastric juice or blood plasma, the potential of sensors is exceptionally large. Focussed on these applications, the interpretation of analytical results is explained. Specific advantages are compared to other analytical techniques. Numerous tables with data provide useful information not easily found elsewhere and make a handy source of reference. Ursula E. Spichiger-Keller is head of the Center for Chemical Sensors/Biosensors and Bioanalytical Chemistry at the Swiss Federal Institute of Technology (ETH) in Zurich.