If you're an angry customer, the last thing you want is another generic offer from the company that has raised your ire. These missteps can irreparably damage a relationship. But companies that know how to collect, analyze and act on customer data will learn to avoid these situations, says my colleague Tom Springer, who leads Bain's Advanced Analytics practice. They'll use that data to calibrate their offers based on a customer's level of advocacy, allowing them to expand relationships with promoters and avoid missteps that might leave detractors feeling exploited. Most companies have vast amounts of customer data—such as the recency, frequency and value of purchases, as well as the number of service calls—but few are using it to its deepen those relationships. Tom is helping companies harness Big Data in ways we couldn't imagine 10 years ago, creating new opportunities to build loyalty.