Because infidelity now affects 80% of all marriages today, more and more people are educating themselves about the signs of infidelity. There are 21 major areas of concern if you think you might have a cheating spouse. These 21 areas of interest correspond to the 21 major categories of infidelity signs covered in Is He Cheating on You - 829 Telltale Signs. And they apply to cheating women as well as cheating men.

Physical Appearance -A cheating spouse will express a sudden desire to look more attractive. He or she will begin to enhance or upgrade their appearance in some way. So if your spouse suddenly embarks on a drastic makeover, it's probably to impress the Other Woman or the Other Man. There are at least 76 different changes in wardrobe, grooming habits, and personal hygiene which indicate your spouse may be having an extramarital affair.

How Your Spouse Relates to You - Your spouse's involvement with someone else will cause him or her to treat you differently -- even on a subconscious level - in over 70 different ways. This is an area where the betrayed spouse who knows what to look for, can spot signs of infidelity that even a private investigator might overlook.

Conversational Clues - What a cheating spouse chooses or refuses to talk about can alert you that he or she is having an extramarital affair. They may mention new people, places or things, while the people, places and things they used to talk about are no longer a part of their conversation. There are 70 conversational clues you can listen for can will give you valuable information about your spouse's affair.

Work Habits - Cheating spouses often use work-related excuses to account for large blocks of time away from home. Working late is the most common cover for an extramarital affair. A change in your spouse's work habits can also indicate that your spouse is involved in a workplace affair, so familiarize yourself with the 39 work-related telltale signs.

Day-To-Day Behavior We all have a routine that we usually follow each day. A cheating spouse will often display a dozen or more of the 92 deviations from their normal pattern of behavior. These deviations are important telltale signs.

Financial Affairs - Affairs cost money. A cheating husband will wine and dine his mistress, entertain her and buy her flowers and gifts. A cheating wife will also buy her lover occasional gifts and spend more money than usual to keep herself looking good. These are just a few of the 52 financially-related telltale signs.

Travel - Travel gives the cheating spouse an opportunity to cheat far from the sight of prying eyes. There are 27 travel-related signs of infidelity including bogus business trips and legitimate business travel that combines a little pleasure on the side. If your spouse's trips occur more frequently