In March 1995 Congress requested the establishment of the Public Safety Wireless Advisory Committee (PSWAC) to focus attention on the issue of interoperability and the demands of the Federal, State and local levels. The Committee identified five key issues that needed to be addressed: operational requirements, transition of technology and service, technology, spectrum requirements and interoperability. The article examines a successful interoperability program in San Diego County, California. The program is used by 121 public safety and public services agencies, and, when the technology is fully operational, will support 10,000 to 12,000 radios. The article reviews the costs and benefits of cooperating multiagency systems, the future of voice and data systems and the problem of overall lack of awareness of standards for interoperability.