This article examines the technological dimensions of border security within the North American continent in the post 9/11 context. The realities of the post 9/11 security environment at the center of the U.S. homeland security lead us to conclude that new technologically-oriented security measures have become the major tendency at the internal and external borders of continents: surveillance devices, biometrics and information technology etc. They have basically emerged as preferred policy solutions to the conundrum of screening for “risk factors” such as terrorists, illegal migrants and drugs into the United States through its international borders while facilitating flows of legitimate people and goods in the age of globalization. With the post 9/11 security environment increasingly common, this may be called a risk-profiling approach.<br> After 9/11, the United States, Canada, and Mexico signed two major agreements: the Smart Border Accords and the Security and Prosperity Partnership of North America (SPP). In 2002 and 2001, the United States signed the Smart Border agreements with Canada and Mexico respectively. They involve multifaceted cooperation on the border security issues, including pre-clearances of people and goods, biometric identifiers, database coordination, information-sharing and other areas. The SPP is a regional framework for trilateral and bilateral cooperation in North America. While this is not a binding legal agreement, nor a formal international treaty, it includes two important agendas related for the post 9/11 context: one reflecting on security and the other on economic prosperity.<br> The United States Visitor and Immigrant Status Indicator Technology (US-VISIT) was launched as an automated biometric entry-exit system in 2004. The US-VISIT program collects biometric and biographical data from foreigners when they not only enter the United States but also apply for the U.S. visas abroad. It represents the proliferation of risk management techniques as a means of regulating mobility in the contemporary war on terror. It is also designed for functioning far beyond geographical boundaries of the U.S. itself. Under the US-VISIT program, the management of border control cannot be recognized simply as “geopolitical and physical bordering measures” of the sovereign states. Rather, it can be understood as “virtual bordering measures” which are seen as obtaining network characteristics. Behind this logic is a recognition that borders and border functions are becoming diffused over everybody life. The concept of “the biometric border (L. Amoore)” represented by US-VISIT along with other technology-driven border security is now becoming common bordering practices of our society.<br> Borders have usually taken for granted in classical IR which assumed “the inside/outside model (R.B.J. Walker)” with which nation-states have long operated. It can be said that the concept of the state has lacked theoretical reflection among IR scholars. We are facing the new challenges by globalization and new security measures which have changed the meaning of the borders. Rather than fixed lines on maps, borders are increasingly understood “portable and mobile machineries” that are embedded in bodies. In this vein, the fundamental shift towards the practices of new bordering measures raises the important task of developing alternative conception of border in the IR.