This article addresses the charged slippery slope accusation that permitting same-sex marriage will inevitably lead to the legalization of polygamy. While same-sex marriage advocates generally distance their cause from polygamy and its disparaging history when responding to such accusations, this article determines whether that response is appropriate, or alternatively, whether the same-sex marriage movement could benefit from linkages between polygamy and same-sex marriage. In conducting the analysis, this article presents a nuanced discussion of marriage and its varying forms. Specifically, it examines the United States' historical regulation of polygamy, interrogates analogies between polygamy and same-sex marriage, compares cross-cultural practices and regulation of polygamy, and reviews the international human rights stance on polygamy and its implications for gender inequality. The article ultimately concludes that while polygamy and same-sex marriage may share some common ground, advocates should continue to distance same-sex marriage from plural marriage to avoid relinquishing the movement's hard-earned cultural capital and societal support. In doing so, however, advocates should avoid maligning polygamy and playing into the cultural narrative that plural marriage is resoundingly barbaric and misogynistic, and instead, direct time and energy toward respecting diversity while fighting for equality.