The demand for personal communications service (PCS) has been steadily growing worldwide. Many technologies for PCS systems have been developed, such as low-tier, high-tier, dual-band, satellite, and microcell/macrocell systems. Every system has its merits in PCS. It is very fascinating to coordinate the merits in PCS systems for the steadily growing users. Therefore, it is important to integrate different PCS systems to provide users better service. In this book, we study issues in integrating PCS networks. Three PCS network services provided by the integration in PCS are described and studied.