Do you know how loyal your customers are? Loyalty means different things to different organizations, and effectively measuring customer loyalty remains a road less traveled by many firms. This report contains a framework designed to help B2C marketing professionals tasked with gauging customer loyalty move past measurement anxiety and identify the metrics to gauge customer loyalty through program health, customer purchase and engagement behavior, and overarching corporate impact. This is an update of a previously published report; Forrester reviews and updates it periodically for continued relevance and accuracy.