The most extensive survey ever conducted on the topic of infidelity has been published in a book called The Normal Bar. The book provides insight into what happy relationships look like and how to develop your own. It also includes the results of a poll of over 100,000 people regarding cheating in relationships. The results are fascinating and shed light on the real reasons people cheat on their partners and how many people are doing it. Who\u2019s Cheating? A survey is not necessarily the most accurate way to get information, but when it\u2019s as large as this one conducted on infidelity, the results can be considered sound. According to the over one million data points collected, 33 percent of men and 19 percent of women have ever cheated on a partner. Interestingly, the respondents considered the difference between a one-night stand in a long relationship and ongoing affairs to be significant. Of those who admitted to cheating, 17 percent of women and 23 percent of men said they only had one slip over the course of a relationship. Why and How We Cheat The survey's most interesting results may be the findings that answer the questions \u201cWhy?\u201d and \u201cHow?\u201d A troubling answer might have most of us worried. Almost half of men surveyed and a quarter of women said that they were attracted to one or more of their partner\u2019s friends and were tempted to act on that attraction. On a positive note, the experts conducting the survey also found that having a satisfying sex life can reduce that temptation dramatically. Not being happy with one\u2019s sex life is a major motivator to cheat. Almost three-quarters of men reported sexual boredom as the main reason for cheating. Another troubling fact to arise from the survey is that business trips are the most common situation in which temptations lead to acts of cheating. Up to a third of men and about 13 percent of women surveyed admitted that a trip for work was when they gave in to a temptation. The number of cheating incidents while away for work peaked for relationships at the six to nine year mark. This seems to be a generally vulnerable period for a relationship. Also troubling about this statistic is that a happy sex life at home didn\u2019t deter people from cheating when away from home. It may be that the opportunity to stray without getting caught is too tempting to resist. For women, a major reason for cheating was running into an ex. About one-third of women who admitted to cheating said it happened with an old flame or an old crush. For men, the rate of cheating with an ex was lower, at about 21 percent. As with cheating on trips, having a happy relationship didn\u2019t seem to matter in cases of cheating with a former partner. Another reason that people cited for cheating included revenge for a betrayal. This was not a common motivation, though. More common was the excuse that monogamy is just too hard to handle, especially for men. Up to half of men reported that regardless of their current relationship status, they just felt they needed more sexual pleasure and that they were entitled to seek it any way they could. The reasons that people cheat are varied, but this large survey concludes that some are seen across the board. Having a happy relationship with a satisfying sex life provides some protection from infidelity, but it isn\u2019t foolproof. Some people will cheat, and they may regret it. What matters is how you and your partner cope afterward, if it happens to you.