A couple of years ago, we asked Inc. 500 CEOs to comment on the maxim "the customer is always right." A slight majority agreed wıth the old rule; the rest believed that there were always exceptions -- customers who make unreasonable demands or behave in outrageous ways. That was in early September 2008, before the stock market fell 4,000 points, unemployment rose above 10 percent, and banks and private equity firms began turning their backs on the kind of small, fast-growing businesses that Inc. writes about. Now, as a consequence of a soured economy and the extraordinary power of the Internet to distribute commentary and criticism, it seems the customer has gotten righter.

Articles that touch on customer service are found in every issue of Inc., and this one is no exception. Nick Sarillo ("Lessons From a Blue-Collar Millionaire") figured out a more efficient way of making pizza so that his takeout customers wouldn't have to wait more than 15 minutes between ordering and heading out the door. ModCloth ("Using Crowdsourcing to Control Inventory"), an online clothing store, asks its customers to help decide which items it will carry. At the travel company Kayak ("The Way I Work: Paul English of Kayak"), co-founder Paul English scrambles to personally answer the red customer service phone so that he can hear directly from the people who use the website.

Then there's Yelp. Yelp is a fast-growing online-review site that allows customers to post comments about stores, restaurants, and the like. Think Zagat, but at length and with very little filter. In our feature "You've Been Yelped," you'll see how small-business owners are reacting to criticism and what the consequences of those reactions are on the business owners' psyches and bottom lines.

Great companies are usually those that put customer service front and center. At last year's Inc. 500 conference, Tony Hsieh, founder of Zappos, spoke with eloquence and charm about the justly famed customer service at his company. If you order over the phone from Zingerman's, as I did several times in December, you'll always find friendly, helpful people on the other end. Superior customer service is crucial when dollars are precious and time is scarce.

But customers, too, have a responsibility to make a commercial transaction easy and pleasant, and if something goes awry, they should make their feelings known in a way that's considerate -- and considered. It's always been possible to complain about a sloppy salesperson or a slow waiter or aggravating help lines, but the Internet makes it possible to criticize in a public forum, which increases the sting of that criticism exponentially. The Web shouldn't be a tool for cleverness or cruelty at the expense of someone else. Care should be taken.

Maybe we should replace "the customer is always right" with a saying that is more appropriate for the times we live in: Customers and companies should do right by each other.