The world is changing ever more rapidly, and the rules of marketing are no different, writes Godin, the field's reigning guru. The old ways--run-of-the-mill TV commercials, ads in the Wall Street Journal and so on--don't work like they used to, because such messages are so plentiful that consumers have tuned them out. This means you have to toss out everything you know and do something""remarkable"" (the way a purple cow in a field of Guernseys would be remarkable) to have any effect at all, writes Godin (Permission Marketing; Unleashing the Ideavirus). He cites companies like HBO, Starbucks and JetBlue, all of which created new ways of doing old businesses and saw their brands sizzle as a result. Godin's style is punchy and irreverent, using short, sharp messages to drive his points home. As a result the book is fiery, but not entirely cohesive; at times it resembles a stream-of-consciousness monologue. Still, his wide-ranging advice--be outrageous, tell the truth, test the limits and never settle for just""very good""--is solid and timely.