The Security and Prosperity Partnership of North America (SPP), signed by Canada, Mexico and the United States in March 2005, proposes a dramatic reshaping of the continent. This is no simple plan for the intensification of economic and security cooperation. The SPP is much more expansive and includes quality of life issues such as education, science and technology, the environment, and health. But what does it mean that there is an emergent concern with biopolitics, that is, with the lives and bodies of the region's citizens, at the trilateral level? How are these citizens being imagined in the new regional vision? What are the implications for states and sovereignty? This paper addresses these questions by turning first to the trope of “partnership” as it emerges in the SPP, and then to the ways that borders and population mobility are being construed. The discourse of “partnership” signals a new political rationality that is reconfiguring the relationship between the North American states, their markets and their citizens. The repercussions for citizens and citizenship are especially significant, and are most clearly apparent vis-à-vis border policies, as I discuss in the following section. While external borders are being hardened against most foreign nationals, mobility across internal borders is becoming more differentiated: more penetrable for some, and impassable for others. The SPP thus promotes a divisive and striated regional space that will help perpetuate the ongoing tensions around illegal immigrants and undocumented workers in North America.