Biochemical engineering is one of the pillars of our basic technological knowledge, with applications in the food, pharmaceutical, biotechnological and water-treatment industries. However, the understanding of the basic thermodynamics of processes that involve cells or other forms of life is still incomplete, and is under investigation in intensive research efforts. Indeed, as a result of incomplete understanding, the need for empirical trials is so over- whelming in process development that extensive use of high-throughput experimental platforms remains unavoidable. This book organizes the fundamentals of the rapidly growing field of biothermodynamics, as it has been presented in a course given regularly over the past 20 years, with the aim of showing how thermodynamics can best be applied to applications and processes in biochemical engineering. It is the authors' hope that the rigorous application of thermodynamics in bio- chemical engineering may be able to greatly rationalize bioprocess development and obvi- ate a substantial fraction of this need for tedious experimental work. As such, this book will appeal to a diverse group of readers, ranging from students and professors in biochemical engineering, to scientists and engineers, for whom it will be a valuable reference.