This extensively updated and expanded second edition contains new chapters on the elctrophysiological measurement of Ca2+ channel activity, enhanced coverage of confocal microscopy, and practical tutorials on two of the most common industrial high-throughput machines, the Fluormetric Imaging Plate Reader (FLIPR), and the FlexStation. All experimental chapters provide readily reproducible techniques for measuring the many dacets of Ca2+ signaling. The protocols follow the successful Methods in Molecular Biology® series format, each offering step-by-step laboratory instructions, an introduction outlining the principles behind the technique, lists of the necessary equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.