"Radio spectrum" refers to the array of channels available for communications transmissions. These channels are a finite natural resource; they cannot be created, purchased, or discovered. Almost all local, State, and Federal public safety communications occur by radio and use spectrum. The scarcity of spectrum for public safety use threatens the ability of the Nation's law enforcement and other public safety personnel to perform their critical missions. Scarce spectrum results in congestion and interference, limiting the ability of public safety personnel to communicate. In responding to this condition, the U.S. Congress encouraged the creation of the Public Safety Wireless Advisory Committee (PSWAC) in June 1995. The PSWAC recognized the immediate need for 2.5 Megahertz (MHz) of spectrum proximate to the majority of current public safety spectrum users and demonstrated the near-term need for an additional 25 MHz of spectrum for public safety allocations. The Balanced Budget Act of 1997 requires the reallocation of 24 MHz of spectrum, currently occupied by television broadcasters, for public safety uses. An additional 73.5 MHz of spectrum is still needed to meet the PSWAC's recommendations.