Ogilvy on Advertising is one of my absolute favorites, and I go back to it regularly. It's also a beautiful book with lots of large photos of campaigns. It's not specifically "marketing" of course, but it covers that area, as well. The funny thing is that a lot of folks in the business writing books today like to present themselves as being innovators and mavericks going against the "old school" of advertising and marketing...but Ogilvy covers a lot of the "new" techniques that folks like Godin and Ries and many others in the web era are pushing. Stuff like directly talking to your customer; the power of personal messages, for example, is covered in great detail in Ogilvy's book. Sure, the technology wasn't there yet to tweet and blog, but the ideas translate quite clearly and easily if you just think about it for a minute. Another "old timer" (who also considered himself a maverick fighting the Ogilvy ways) is George Lois. His book "What's the Big Idea?" is full of great stories of reaching a market on the cheap.
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