Polyfidelity

Polyfidelity (also sometimes called polyexclusivity) is an intimate relationship structure where all members are considered equal partners and agree to restrict sexual activity to only other members of the group.

Though the practice itself, like monogamy, has existed throughout known history, the term polyfidelity was coined in the "New Tribe" of the Kerista Commune. The community expected all of its members, within bounds of gender and sexual orientation, to be sexually active with all other members, and for exclusive relationships not to be formed within the group.

Polyfaithful relationships are, like monogamous relationships, closed in the sense that partners agree not to be sexual with someone not in the relationship. The difference is that more than two people are included in the closed group. New members may generally be added to the group only by unanimous agreement of the existing members, or the group may not be interested in further expansion.

Rather than being a subtype of the more general polyamory, polyfidelity is an outgrowth of monogamy, most often developing from an established closed couple seeking to add one or more individuals or another couple. In this sense, it expands upon standard practices and beliefs of monogamy rather than creating a restricted form of nonmonogamy.

Previous to the Kerista Village experience, people would have likely called this arrangement "complex marriage" or simply a "group marriage." Adding new members would typically require consensus rather than violate the fundamental compact. The modern, broader term polyamory was coined later, in the early 1990s.

In Proposition 31, Robert Rimmer presents two married couples who form a group marriage as an alternative to divorce when they are forced to deal with sexual infidelity. Late in his life, Rimmer claimed to have lived for many years in such a two-couple relationship.

A commonly cited advantage of polyfidelity is the ability to fluid bond among more than two people while maintaining relative safety regarding STDs, so long as any new members are sufficiently tested before fluid bonding with the group, and keep their commitments. This would have health advantages similar to monogamy, although risks rise somewhat with each person added.

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