Polyfidelitous

Polyfidelity 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.

The practices and beliefs underlying polyfidelity have long existed, but in uncodified fashion. The Oneida Commune of the mid-19th century practiced complex marriage, encouraging individual members in the freedom to have multiple ongoing sexual relationships within the community, as an expression of their beliefs and religious faith. This was occasionally referred to as a group marriage, a term brought back to popular recognition by the 1974 publication of Group Marriage: a study of contemporary multilateral marriage by Larry Constantine and Joan Constantine.

In Proposition 31 (1968), 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 years in such a two-couple relationship.)

The term polyfidelity was coined in the "New Tribe" of the Kerista Commune. The community at first 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. Adding new members would require consensus rather than violate the fundamental compact.

The broader term polyamory was coined later, in the early 1990s.

Polyfidelitous 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.

While being a subtype of the more general polyamory, polyfidelity can resemble monogamy in its relationship power dynamics, attitudes towards autonomy and group consent, as most often polyfidelity develops from an established closed-monogamous couple seeking to add one or more individuals or another couple. In this sense, polyfidelity expands upon standard practices and beliefs of monogamy while still being categorically polyamory.

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