Few companies show their financial statements totheir customers -- they're afraid that if customers find out what their margins are, they will try to negotiate better prices. That may be the case, but it may also be true that if you're delivering value, it's at a price customers are prepared to pay -- otherwise they wouldn't be your customers. And presumably, they have an interest in keeping their vendors happy.

There can be real value in being completely open with customers. That's why Manco, a fast-growing distributor of duct tapeand other consumer products, based in Westlake, Ohio, tracks its costs, customer by customer, and then shows thefigures to them. Each customer sees exactly what Manco makes on its business, which is exactly the point. Customers cansee, for instance, that they aren't paying for somebody else's freight. That, says Tom Corbo, president of Manco, gives thecompany a competitive advantage.