This detailed book provides state-of-the-art protocols to facilitate the construction of synthetic protein switches for a variety of applications in biotechnology and basic research. Beginning with general strategies, the volume continues with coverage of peptide switches, fluorescent and bioluminescent sensors, β-lactamase sensors, proteolytic sensors, optogenetic switches, as well as cellular signaling switches.  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.