A young woman tells a focus group that Diet Coke is like her boyfriend. A twenty-something tattoos the logo of Turner Classic Movies onto his skin. These consumers aren’t just using these brands. They are engaging in a rich, complex, ever-changing relationship, and they’ll stay loyal, resisting marketing gimmicks from competitors and influencing others to try the brand they love. How can marketers cultivate and grow the deep relationships that earn this kind of love and drive lasting success for their brands?