Complex marriage

Group marriage (a form of polyfidelity) is a marriage-like arrangement between more than two people. Usually consisting of three to seven adults, all partners live together, share finances, children, and household responsibilities.

Depending on the sexual orientation and activity of the members, all adults in the family may be sexual partners. For instance, if all members are heterosexual, all the women may have sexual relationships with all the men. If the members are bisexual, they may have sexual relationships with the women as well as the men.

Group marriage implies a strong commitment to be faithful - by only having sex within the group and staying together long term. Family members may be open to taking on new partners, but only if all members of the family agree to accept the new person as a partner. The new person then moves into the household and becomes an equal member of the family.

Currently, the most common form of group marriage is a triad of two women and one man, or two men and one woman. However, there have recently been a number of polyfidelitous families formed by two heterosexual couples who become a four-some and live together as a family.

Line marriage is a form of group marriage found in fiction in which the family unit continues to add new spouses of both sexes over time so that the marriage does not end.

"Group marriage" can more informally describe a polyfidelitous relationship ("… our little group marriage") when no claim to being married in formal legal terms is made.

In most countries, it is legal for three or more people to form and share a sexual relationship (subject sometimes to laws against homosexuality). However, no Western countries permit marriage among more than two people. Nor do they give strong and equal legal protection (e.g., of rights relating to children) to non-married partners – the legal regime is not comparable to that applied to married couples. Individuals involved in polyamorous relationships are considered by the law to be no different from people who live together, or "date", under other circumstances.

For a map with the legal status of group marriage in a particular country see Legal status of polygamy.

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Wikipedia