The articles in this section are based on a Social Science History Associationroundtable organized in 2008 in response to Donna R. Gabaccia'spresidential call “It's about Time: Temporality andInterdisciplinary Research” (see Gabaccia 2008; see also Gabaccia 2010).Her emphasis on questions of periodization resonated with concerns with which wehad grappled for a decade. The questions that the roundtable and these articlesaddress initially emerged from our experiences as teachers of a course on worldhistory with a temporal frame of a few centuries (1450 to the present). But thecourse that really forced us to confront the challenges of periodization is onewe introduced in the fall of 2009 on “the family from 10,000 BCE to thepresent.” In trying to connect research from around the globe on thedomestic group as a site of world history to narratives that begin with humanorigins, we were struck by the inappropriate presumptions embedded in mostconventional periodizations. Our inherited vocabulary of terms to describe eras,ranging from “the Neolithic revolution” to “earlymodern,” implicitly place all regions of the globe on a yardstickmeasured against European temporalities and based on activities typicallygendered male.