The National Science Foundation's Directorates for Engineering (ENG), Computer and Information Science and Engineering (CISE), Mathematical Physical Sciences (MPS), and Social, Behavioral and Economic Sciences (SBE) are coordinating efforts to create fundamental understanding that will enablecontinued effective use of an essential common resource, the electromagnetic spectrum. Existing approaches to spectrum management and regulationhave struggled with the ever-increasing demands for spectrum created by continual emergence of new scientific, military, and commercial applications, powered by steady advances in wireless technologies. Development of fundamentally new models and paradigms of spectrum access and management, along with enabling technologies, is needed before it becomes too costly to accommodate new innovations and essential services, or too late to sustain the digital transformation and growth of key industries and public services. This program seeks to develop the intellectual capital enabling the U.S. to smoothly and quickly transition to effective new ways of using and managing the radio and optical spectrum after the end of the current spectrum era of long-term exclusive-use license auctions, thereby sustaining and advancing the social, economic, scientific, and U.S. national leadership benefits derived from the electromagnetic spectrum.