The most obvious way to catch a cheating spouse is also the most expensive.  You can hire a private detective.  This may pay off if your spouse is truly cheating on you, but you can spend a lot of money finding out.

Have a friend of yours follow them.  This can also be very costly on the friendship.  Most of our friends work during the day when most cheating occurs.  If you do find a friend willing to do this, how long will they be willing to do follow them?  It can take months before it’s the right time and the right place to catch somebody.

During the course of most affairs, a call is made from the home phone to the cheating spouses lover.  You can often find out if your spouse is cheating simply by recording your home phone.

By using a recorder that is line sensitive (one that senses the voltage of the phone line to know if it is in use or not) you can record all of the phones on that telephone line. 

You can hide the recorder almost anywhere.  You can hide it in a drawer, in the basement, attic, or even in plain sight.  Have a recording system on your desk to record notes, conference calls, dictation, or other work related things is not uncommon.  There are even recorders you can hide in your PC!

By making the investment in a good phone recorder, you can use it for other situations like knowing whom your kids are talking to.  Monitoring your teenager’s relationships, and more.