The emergence and rapid uptake of cloud computing services raise a number of legal challenges. Recently, there have been calls for regional clouds; where policy makers from various states have proposed cloud computing services that are restricted to serving (only) their particular geographic region. At a technical level, such rhetoric is rooted in the means for control. This paper explores the technical considerations underpinning a regional cloud, including the current state of cloud provisioning, what can be achieved using existing technologies, and the potential of ongoing research. Our discussion covers technology at various system levels, including network-centric controls, cloud platform management, and governance mechanisms (including encryption and information flow control) for cloud providers, applications, tenants, and end-users.