"Click Fraud," gets cover story treatment in the October 2, 2006 issue of BusinessWeek.

It's an insidious problem, one exacerbated by the fact that it often is not readily detectable. The BusinessWeek focuses largely on the experiences of Martin Fleishman and his site www.MostChoice.com.

Martin is a firm believer in online advertising, but he's had that faith rattled by the discovery that of the $2 million he's paid Google and Yahoo!, at least $100,000 was the result of click fraud. And the only reason he ever picked up on it was because he took the time to check where the clicks were coming from and discovered a number coming from such places as Botswana, Mongolia and Syria.

Had he not poured through his data, he would have remained oblivious of the problem.

Basically, as near as he can determine, at least 5% of the clicks he paid for were fraudulent. He may actually have missed a few that were better hidden in the data; it's current estimated that fraudulent clicks can amount to as much as 20% of an ad's clicks.

So what's an advertiser to do?

Well, you can pour through the data, as Martin did, and try to discern which clicks might be fraudulent, but that can be time-consuming, costly and, if you don't know what you're looking for, fruitless.

You can also turn to companies that have developed fraud detection technologies, such as that offered by Zunch Communications' popular Click Fraud Detective.

As Google, Yahoo! and other search engines continue to seem reluctant to deal with the issue head-on (in the BusinessWeek story, Martin recounts how Google refused to do anything for some time, despite compelling evidence he provided regarding fraudulent clicks), using an established professional service like Click Fraud Detective is a good bet for both detecting click fraud and recovering from the search engines for its costs.