Research and application development in the field of chemical and biochemical sensors is still experiencing rapid growth. However, the experiences of the last decade have shown that the successful development of such sensors, which can withstand the harsh routine conditions in various application areas, is only possible when chemists and engineers collaborate. Therefore, the aim of this textbook is to present the technology and application of chemical sensors in a strictly systematic yet highly practical manner to both chemists and engineers, as well as food and biotechnologists. The interdisciplinary approach successfully bridges the different ways of thinking in chemistry, physics, and engineering.