In the intense debate over spectrum governing regimes, one of the most 
divisive issues is whether new technologies will eradicate spectrum 
scarcity and allow everyone to access the airwaves as a commons resource 
without mutual interference. This paper examines the technical 
characteristics and policy implications of four emerging technologies 
(mobile ad hoc networking, ultra-wideband radio, smart antennas, and 
software radios) often cited by commons proponents as enabling 
technologies for the commons regime. A more detailed and balanced 
examination shows that some current technological limitations and 
implementation issues are likely to lead to a long transition process; 
therefore plans addressing issues during the transition process are needed 
to back up the current commons proposals.