This book provides comprehensive methods and protocols about enzyme design. The chapters are grouped by main topic, starting with methodologies describing library preparation and screening, state of the art techniques in directed evolution and rational design, followed by examples of immobilization of enzymes on sustainable polymers, as well as biocatalytic conversions mediated by homogenous enzymatic preparations or whole cells. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.