15. Groundswell

15. Groundswell

By Charlene Li and Josh Bernoff
(Harvard Business School Press — $29.95)

Li and Bernoff, both of consultant Forrester Research, here provide a case-study-rich look at social networking, the Web phenomena that’s behind the likes of Facebook and YouTube. The "groundswell" in question, they say, is "a social trend in which people use technologies to get the things they need from each other, rather than from traditional institutions like corporations." This can cause a crisis for business—or an opportunity. Among the companies they show as profiting from the trend are Procter & Gamble, Best Buy, and Dell.