With a device he calls STAS (Short Term Advertising Strength)--a measure of the immediate effect of advertising on sales--the author demonstrates that the strongest ad campaigns can triple sales, while the weakest campaigns can actually cause sales to fall by more than 50 percent. He exposes sales promotions as wasteful, especially when they are unsupported by advertising, and also demonstrates the strong synergy that can operate between advertising and promotion when they are planned and executed in an integrated fashion. When Ads Work offers eye-opening research and practical information that no one who studies advertising or spends advertising dollars can afford to ignore.