Some good ways to catch a cheater often involve monitoring the suspected cheater with physical surveillance, monitoring the behavior of the cheater's partner and online monitoring. The use of technology to spy on a suspected cheater is also an effective way.
Surveillance often requires the services of a private investigator who then reports about the movements of the partner. It is possible to catch a cheater by observing his behavior. Cheaters most likely change the way they behave toward their partners, sometimes becoming withdrawn, nervous and secretive.
Though it is likely to break all trust, it is possible to spy on a partner's phone records, messages, call log and emails, which makes it easy to notice anything that looks suspicious. Eavesdropping and recording the cheater's conversations can also help put him on the spot.