Remember when marketing was simple? Your division operated in a manageable geographic region. You defined your consumer targets by age, say, and by income. If you were in a business-to-business market, you divided up companies by size.

But the wild proliferation of brands and channels in rapidly globalizing markets now flusters even the most sophisticated marketers. In this environment, how should your sales force tailor its strategies to its accounts? Different customers have different attitudes, needs, and preferences, but the old distinctions no longer take you very far. What should you be looking at today? The current purchasing behavior of your customers? The benefits they seek to obtain? Demographics or its business-to-business equivalent: "firmographics"?

Ford’s Model T strategy—any color you wanted, so long as it was black—worked until customers had an alternative. Soon-to-be-deregulated utilities, among other companies, are now miserably aware of this reality. How will the utilities build loyalty among the most profitable customers before competition takes them away? Utilities had so little need for marketing in the past that some know very little about them and have no idea what products and services might keep them loyal after the coming of choice. Companies often address this problem...