Carl Warren, Connecticut, USA

A Not dead, but different.

Time was, you could "earn" a customer's loyalty with tickets to a big game, a Disney World vacation or even a nice dinner a few times a year.

And you could pretty much keep that loyalty with what used to be called belly-to-belly selling or, put less graphically, relationship building.

You'd listen to your customers' dreams and worries, visit them to see how your product fit their needs and trouble-shoot their problems. In more competitive situations, you'd add the sort of extra manufacturing and design services you mention in your letter.

And, usually, such partnering was enough to keep customers in the fold. Yes, price mattered in those halcyon days. Sometimes it mattered a lot. We're only talking about, say, 10 years ago. But it never mattered like it matters in today's fierce economy. The internet, in particular, has made pricing transparent and purchasing global.

And as a result it is becoming a buyer's world.

But we're not ready to bury customer loyalty, only to redefine it from a transaction to a two-way street. With the transaction approach to loyalty, you give your customers competitive pricing, high quality and excellent service. They give you repeat business in return.

It's a nice deal. . . until someone comes along with slightly better pricing, quality or service. Then it's ground zero again as you try to win your customer back, almost as if you've never met before.

With the two-way-street approach to loyalty, you and your customers don't have a deal as much as you Q A have mutual dedication. Because you, the seller, are not delivering on just price, quality and service. You are demonstrating intense loyalty to your customer by giving him a comprehensive, inimitable way to win. Better productivity. Lower inventory. More innovative products.

You are delivering something . . .anything . . . that makes you indispensable to your customer's success in the marketplace. Then, and only then, will you get complete loyalty in return.

Now, you may be thinking, "We did that! We built dedicated plants. We designed special packaging."

To which we'd ask: But did those services . . . no doubt costly to you . . .change the game for your customers? Did they allow your customers to expand into profitable new markets or catapult old competitors? It seems unlikely; how could they have walked away?

They couldn't have.

Modern loyalty, then, ultimately comes down to that old saying: "What goes around comes around."

The more fervently committed you are to making your customers win big in the long haul . . . not just meeting their immediate demands . . .the more fervently committed they will be to you.

That's a hard order, of course. But given the direction of the ever more competitive global economy, a twoway-street approach to customer loyalty is the only road to take.

Jack and Suzy Welch are the authors of the international best-seller Winning. You can email them questions at winning@nytimes. com