Book excerpt: Radar and Communication Spectrum Sharing addresses the growing conflict over use of the radio-frequency spectrum by different systems, such as civil and security applications of radar and consumer use for wireless communications. The increasing demand for this finite resource is driving innovation into new ways in which these diverse systems can cohabit the spectrum. The book provides a broad survey of recent and ongoing work on the topic of spectrum sharing, with an emphasis on identifying the technology gaps for practical realization and the regulatory and measurement compliance aspects of this problem space. The introductory section sets the scene, making the case for spectrum access and reviewing spectrum use, congestion, lessons learned, ways forward and research areas. The book then covers system engineering perspectives, the issues involved with addressing interference, and radar/communication co-design strategies. With contributions from an international panel of experts, this book is essential reading for researchers, engineers and advanced students in radar, communications, navigation, and electronic warfare whose work is impacted by spectrum engineering requirements.