Although I’m a gay male therapist who’s worked with gay clients for 30 years, I don’t purport to know everything there is to know about sex among gay men any more than a straight therapist knows everything about heterosexual sex. But I do have a certain level of professional experience around a particular area of interest among my friends and colleagues—open relationships, or arrangements in which both partners agree to allow each other to have sex with people outside the primary relationship.

For gay men, open relationships aren’t unusual, but the arrangements vary. Some couples agree only to three-ways with both partners present. Other couples agree they can have sex with other people without the partner being present. Some agree to only a one-time hookup with another person, and others allow repeated hookups. But just because something is common doesn’t mean it’s right for everyone.

When a couple in a troubled relationship considers opening up the relationship as a way to fix their problems, an alarm sounds for me, and I often discourage them from doing so. But even for healthy couples, opening up a relationship in a way that’s not destructive is hard work and requires a great deal of communication around what is and isn’t acceptable. Thus, I invite my clients interested in taking this leap to take part in a contractual negotiation in which they agree to make the primary relationship the priority. They talk out the terms and limitations of the open…