When it comes to making same-sex friends, we tend to like others who are similar to us. For example, we’re more likely to be friends with people who share our personalities, values, and interests. But what about sexual history? When evaluating potential friends, we could look for someone whose sexual experience matches our own values and past, or we could avoid those with lots of previous partners. And would you want your new friend hanging out with your romantic partner, or would that be a threat to your relationship? Of course, much of this may depend on whether you are man or a woman.