In this extended introduction to the Special Issue, we want to reflect upon the vibrant and growing field of scholarship on the history of trafficking that, in one way or another, grapples with these terms while attempting to understand the structures, cultures, laws, and lived experiences that underlay them in different times and places. We begin by examining this scholarship’s roots in work on women’s prostitution in the nineteenth and twentieth centuries and move on to explore particular flashpoints within this historiography: the places where trafficking, used in any normative sense, grows increasingly difficult to pin down and explain. Caught up within racialized concepts of migration, belonging, and citizenship; complex ideas about gender, sex, and labor; and troubling analogies of enslavement, trafficking’s history as a term, one could argue, has little useful explanatory power, other than the way it reveals the socio-political contexts in which it was deployed. The articles in this special issue cover the period roughly between 1880 and 1980, taking us from the late nineteenth century, when concepts of trafficking and exploited prostitution were first being articulated and codified, to the late twentieth century and the resurgence of “trafficking” as a subject of concern during a period of geopolitical upheaval and increased migration. This special issue showcases some of the newest work on migration, sex, and intimate labor, and in their own way, all the articles complicate the terms we use to articulate these phenomena not only in the past, but also in the present.