One ghost-hunting group called 'A Midwest Haunting' based in Macomb, Illinois, reported that the number of people taking its tours had tripled, jumping from about 600 in 2006 to 1,800 in 2008. The paranormal boom is such that some small ghost-hunting related businesses are enjoying increased profits through podcast and website advertising, books, DVDs, videos and other commercial enterprises. Many offer electromagnetic field (EMF) meters, infrared motion sensors and devices billed as 'ghost detectors'. Small businesses offering ghost-hunting equipment and paranormal investigation services increased in the early 2000s. Despite its lack of acceptance in academic circles, the popularity of ghost-hunting reality TV shows has influenced a number of individuals to take up the pursuit. The Atlantic Paranormal Society reported a doubling in their membership in the late 2000s, attributing this to the television programs. Ghost hunting was popularized in the 2000s by television series such as Most Haunted and Ghost Hunters, combined with the increasing availability of high-tech equipment. Psychic researcher Harry Price published his Confessions of a Ghost-Hunter in 1936.

Paranormal research dates back to the nineteenth century, with organizations such as the Society for Psychical Research investigating spiritual matters. History British psychic investigator Hereward Carrington with his 'ululometer' ghost detector, in 1922. Ghost hunters also refer to themselves as paranormal investigators. Other more traditional techniques are also used, such as conducting interviews and researching the history of allegedly haunted sites. Ghost hunters use a variety of electronic devices, including EMF meters, digital thermometers, both handheld and static digital video cameras, including thermographic and night vision cameras, night vision goggles, and digital audio recorders. The practice is considered a pseudoscience by the vast majority of educators, academics, and science writers. No scientific study has ever been able to confirm the existence of ghosts. Ghost hunting has been heavily criticized for its dismissal of the scientific method. Typically, a ghost-hunting team will attempt to collect evidence supporting the existence of paranormal activity. Ghost hunting is the process of investigating locations that are purportedly haunted by ghosts.

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