This would seem to be the sensible alternative to marriage.
It comes about in different situations. Some people have something like this going for themselves, or it exists for themselves just for a little while.
Most often though it seems to require some kind of structure, some kind of leadership and rules. Often this amounts to what people commonly call cults.
But even straight P4P and Mistress Keeping can be seen as moves in that direction, breaking down the strict rules of monogamy.
Read yesterday about the group led by Rajneesh. It was one of the larger scale and longer running polyamorous arrangements.
SJG
Nejat Talas nejattalas.com
Pink Floyd youtube.com
The Thrill is Gone + Summertime (BB king + George Gershwin cover) REALLY GOOD! youtube.com
The late Stan Dale was a long running opponent of compulsory monogamy. He decride what he saw in middle schoolers, "going steady", learning to practice monogamy.
www1.hai.org
I think he had a long term relationship with two women.
And then at some UU churches there are people practicing polyamory, though I don't know that it has gone beyond one man and two women.
Dale talked about Swinger's Clubs, the Creepy Republican Wife Swappers. He said that that is our right wing. But we also need a left wing, and that is polyamory.
Usually it does seem to need some sort of organizational structure. And of often such groups do not last very long, or go not last beyond the life of the founders.
Rajneesh's followers are still operating in India.
osho.com
But if we want the same, we don't need to use Rajneesh's name, or travel to India.
And it had always seemed to me that eventually feminism would become something which supports polyamory. Turning to yuppieism is a corruption of feminism.
SJG