This post is a twofer, addressing both That 70s Show and the shortlived series Swingtown. Both are early 2000s (in the case of That 70s Show, starting in late 1990s. For the tags, I’m going to mark it as 2000) representations of a particularly type of non-monogamy in the 1970s.
First, what is Swinging? “Swinging,” in the 1970s US, was associated with terms like “wife-swapping” and “key parties.” In short, it refers to situations in which two (or usually, more) heterosexual couples form a socio-sexual network in which people within the network have a emotional relationships with one person (their spouse) but sexual relationships with others who have their own separate emotional relationships. In theory, relationships with non-spouses were purely sexual, and served no threat to the emotional monogamy of the marriage. In practice, oral history evidence suggestions, this was not necessarily the case. However, it was not exactly the free love movement that it is often portrayed to be.
Indeed, the actual swinging movement of the 1970s differs significantly from the portrayals we are about to explore, which say more about writers and viewers in the 1990s-2000s than the swingers’ in the 1970s. A 1971 one study locates swinging among “basically middle-class, and essentially conventional people,” with a “somewhat bureaucratized and decidedly unfestival-like quality (Walshok, p. 490). This study stresses the “one dimensional quality of middle-class deviancy,” in that swingers participate only in swinging, and in no other marginal behavior (Walshok, p. 492). “Only occasionally,” it explained, “are swingers found at the forefront of movements for such things as abortion reform of changing legislation pertaining to homosexuality (Walshok, p. 494).”
What about in these 70s themed shows? Spoilers below the cut.
For more on this topic, see this AV Club post on “Surprise TV Encounters with the Polyamorous.” Good stuff.