Key elements of the North American Free Trade Agreement (NAFTA) deal with temporary labor mobility. Ideally, NAFTA status provisions should make the temporary movement of professionals easier across the border of all NAFTA countries. However, in the case of emerging sectors such as high technology and the creative industries, it is arguably not the case. Within the context of recent literature on cross-border trade, city regions, economic clusters, international labor mobility, and post-September 11 security measures, this book probes the dynamics of transitory immigration of 'knowledge-workers' between the North American west coast city regions of Vancouver, Seattle, and the greater San Francisco Bay and Silicon Valley area, namely, Cascadia. With particular attention given to the experiences and strategies of the high tech firms that must move highly skilled workers across the Canada-US border, this book draws from 80 in-depth interviews with Canadian and US immigration officials, immigration attorneys and executives and professional staff of new technology firms and Fortune 500 companies. It develops and presents new models towards the development of an innovation cross border region, and recommends new policy approaches. Ultimately, it explores whether or not the Canada-US border is an impediment to the development of cross-border high-tech clusters. This comprehensive book will serve as a critical resource for academics in geography; political science; international relations; global studies; economics; international business and law. It will also strongly appeal to practitioners such as professional immigration lawyers, corporate firms, and governmental policy makers alike.