Our National Survey of Lesbian & Gay Couples shows us that female respondents heavily favored exclusive sexual relationships. Exclusivity was also the preferred mode for male couples, however, the men made far more exceptions.

For comprehension purposes, our survey used the term “monogamy.” While the term is widely used to describe a “sexually closed relationship,” it properly means “individuals who only marry one person” (as opposed to “polygamy”), which does not describe sexual agreements.

In our survey results we found no correlation between “monogamous” relationships and the “Quality of Relationship” or the “Degree of Commitment.” We did find, however, that agreement-breaking respondents were more likely to argue, suffer abusive behavior, and to give their relationship lower quality ratings. They also gave lower ratings to sexual interaction with their partner.

In “The Male Couple’s Guide to Living Together,” Eric Marcus emphasizes that successful sexually open couples do not “use outside sexual involvements to avoid problems in their relationship or use outside sex as a substitute for sex with their lovers.”

He suggests these guidelines that can help secure a sexually open relationship:

• Each partner’s desires should be clearly spelled out, not assumed.
• Unless both partners agree to a sexualy open relationship — and feel good about it — outside sex may well interfere with the primary relationship.
• Once boundaries are established, their effectiveness should be periodically reassessed.
• If jealousies or fears surface, it is important to discuss them immediately.

In “Lesbian Couples,” therapists D. Merilee Clunis and G. Dorsey Green stress that sexually open relationships almost always need structure and guidelines to protect the primary relationship. But the rules need not be cast in stone.

“Usually the couple agrees to a flow between monogamous and non-monogamous,” say the authors, “depending on how the women feel at any given time. So, if one partner is not feeling secure, she may ask that they be monogamous for the next few months. When she feels stronger, they open the relationship again.”

Researchers McWhirter and Mattison studied 156 male couples (as reported in “The Male Couple,”), and drew up a list of the various agreements they encountered among sexually open couples:

• All outside sex follows safer sex guidelines.
• Sex is only allowed at particular places, such as the baths.
• No sex with mutual friends.
• Sexual encounters must not interfere with the couple’s customary or planned time together.
• Sex is permissible only when one partner is out of town.
• Sexual encounters are always verbally shared with each other.
• Sexual encounters are never spoken of.
• Talking about outside sex is expected, but at least 48 hours must pass before any discussion is permitted.
• Outside sex is only allowed with advance agreement with one’s lover.
• No emotional involvement with outside sex partners.
• Outside sex is allowed only when both partners participate.
• Outside sex is never permitted at home.
• If sex occurs at home, then each must simultaneously have a sex partner of his own.
• Sex is permitted at home, but not in the bedroom.
• Secondary emotional relationships with sexual friends are allowed, but only when including one’s lover.

Keeping agreements is the single most critical factor in any relationship.