Every business knows that the best customer is a happy customer. They return again and again, bring their friends and family, and deliver tons of free advertising via word of mouth and social media. But in order to grow that loyal base, you must be keenly aware of your customers' needs and preferences. Drawing on the latest research in the exploding field of positive psychology, Columbia Business School professor Bernd Schmitt offers three unique approaches any business can use to turning a casual customer into a committed fan: . The Feel-Good Method: Use the experience of pleasure and positive emotion to hook new customers, and watch those feel-good moments transform an impulsive buyer into a committed loyalist. . The Values-and-Meaning Method: Attract passionate customers by appealing to their core values, like being socially responsible, protecting the environment, or living a simple life . The Engagement Method: Get customers to notice a unique or limited offer, immerse them in the experience, and have them share it with friends and family. Schmitt shows marketers, brand managers, and entrepreneurs how to design an authentic and successful campaign that will reach, grow, and sustain a devoted base of customers.