I ran into this article from which I learned some facts about polyamorous relationships I did not know before:
Polyamorous relationships. What are they? Who do they involve? Are they common?
Research says that as many as 5 percent of Americans are currently in polyamorous relationships, or consensual non-monogamy – which involves permission to go outside the relationship for romance or sex.
This population has been around for a long time, but it’s just now popping up in mainstream culture as society becomes more accepting of alternative lifestyles. There have even been several TV shows (both scripted and documentary) on the subject. Read the full article here