The advent of the Internet transformed the private-eye industry, shifting its focus from background checks (which can now be completed for a small price on myriad Web sites) to surveillance.

Skipp Porteous, president of New York–based Sherlock Investigations, says much of his business is derived from spouses who suspect infidelity. “A lot of times we get calls from a wife whose husband is coming to New York, usually on business, and she’s afraid he’s going to fool around,” Porteous says. “So she hires us and we get the goods.” (Incidentally, Porteous says women are right in their suspicions about 90 percent of the time; when men think their wives are cheating, they’re usually wrong.)

Sherlock dispatches teams of two licensed private investigators, experts at blending into crowds and going unnoticed, to follow the suspected cheater and snap photos. In one case, a woman from Bermuda hired Sherlock to follow her husband while he was in New York. Investigators took pictures of him with six prostitutes (at once) and e-mailed them to their client before her spouse returned home.

Additionally, since the Internet has enabled people to easily purchase illegal audio and video transmitters, Sherlock has seen a boom in “bug sweep” business, especially among celebrities who believe the paparazzi have infiltrated their homes or cars. As new technologies emerge, experts expect intelligence and counterintelligence methods to grow in sophistication, and generate even more job opportunities for a new generation of supersleuths.

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