Protein engineering is the rational modification or redesign of proteins using genetic engineering. Thus, it is now possible to modify enzyme specificities, remodel antibodies, and redesign many multi-domain proteins for therapeutic purposes. While the procedures for the introduction of mutations have become routine, predicting and understanding the effects of these mutations can be complicated. This volume provides a comprehensive guide to the methods used at every stage of the engineering process, from the choice of mutation strategy, through protein stability studies, to critical evaluations of mammalian, yeast, and bacterial host expression systems. Protein Engineering: A Practical Approach is the first practical guide to this fascinating mixture of molecular biology, protein structure analysis, computation, and biochemistry. It combines a thorough theoretical foundation with detailed protocols and will be invaluable to all research workers in the area, from graduate students to senior investigators.