Cheating is common. For instance, among heterosexual married persons in the United States, research generally indicates that somewhere between one in four and one in five people report having cheated on their partner previously [1]. However, estimates of cheating prevalence can vary widely across studies depending upon how “infidelity” is defined. It turns out that not everyone perceives the same actions in the same way. As some evidence of this, let’s examine the results of a new study in which people were asked to determine what they think constitutes cheating in a relationship.

In this study, 456 heterosexual college undergraduates were given a list of 27 interpersonal behaviors and were asked to imagine that someone in a long-term relationship engaged in that behavior with a person of the other sex [2]. Participants then rated the percentage likelihood that the behavior was indicative of cheating on a scale ranging from 0% (clearly not cheating) to 100% (definite cheating). The behaviors fell into three different classes: sexual interactions (e.g., kissing, oral sex), emotional closeness (holding hands, sharing secrets), and casual interactions (e.g., hugging briefly, loaning each other money).

Below, you can see how the behaviors stacked up. People were largely in agreement that very erotic and physically intimate behaviors are likely to indicate cheating and that more casual encounters are probably more innocent. However, it is important to note that people’s ratings of the behaviors depended upon their sex and their attachment style. Specifically, women were more likely than men to say that emotionally intimate behaviors (e.g., sending erotic texts, holding hands, forming emotional bonds) represented cheating. In addition, persons with an anxious attachment style (i.e., people who fear being abandoned by their romantic partners) were more likely to label casual behaviors as cheating than those who are more secure.