Updated with many of the new approaches that have been transforming the field, including readily reproducible immunoassays, fluorescence-based assays, high-throughput methods, protein modification assays, lipid second messenger assays, and chromatin immunoprecipitation techniques. The book offers step-by-step laboratory instructions, an introduction outlining the principle behind the technique, lists of the necesary equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.