Angel Customers & Demon Customers: Discover Which Is Which, and Turbo-Charge Your Stock

Conventional wisdom holds that the customer is always king (or queen), but not all customers are created equal, write authors Selden (a consultant) and Colvin (a Fortune editor-at-large); in fact, some may be hurting your business (e.g., people who phone customer service lines thousands of times in a single year). So, they argue, it's smart strategy to figure out which customers are most valuable to you, and to lavish your attentions on them. The authors point out a number of companies that are reorganizing how they operate, like Best Buy and Toronto-based Royal Bank. The tone is exceedingly businesslike; sans colorful narratives or rhetorical flourishes, the authors march stiffly through the points they want to make. It's unclear sometimes how behavior should be altered by this philosophy: should you, for example, refuse to do business altogether with unprofitable customers? But the book's central thesis manages that rare mix of being both surprising and eminently reasonable.