The Regional Communications System (RCS) went online in 1998 delivering a network of continual communications between law enforcement, fire department, and EMS personnel during critical incidents. The RCS can provide a number of critical communications capabilities that the cellular and landline systems are unable to achieve, and the RCS is designed to operate in either digital or analog modes. San Diego’s move to a regional, shared communications system in 1995 is presented. The major obstacle encountered for San Diego when creating a new communications approach was acquiring political support. The lessons learned from two high school tragedies in California showed how the planning and practice of an emergency response plan are crucial. The plan must be reviewed and practiced often. In addition, interoperable communications is a vital component. Agency personnel must be able to talk with one another throughout an emergency. With a shared infrastructure, shared frequencies, and a mutual aid plan this can be achieved.