Publisher Summary Unbounded mobile communications (UMC) solutions are currently on the market and meet many customer mobile communication needs. Whether consumer (controlled by the cellular provider) or enterprise (controlled by the enterprise), all the UMC solutions seek to provide an unbounded experience with telephony providing a consistent feature set regardless of physical location, freeing the user from concerns of coverage, location, or features. The evolution of UMC solutions has gone quickly beyond the simple goal of providing a seamless bridge between the fixed and mobile telecommunication worlds, and the future holds promise of being able to carry a personal and professional communicator to be available at all times, regardless of where you are on the globe. Analysts have projected that by 2012 there will be some 5.8 billion cellular phones in use on the planet, many of which will be dual-mode, providing that extended wireless coverage needed by an ever-growing mobile community of travelers, workers, vendors, customers, associates, family, and friends. Wireless infrastructures that blanket the globe will be the backbone of the worldwide UMC services. Once these wireless “highways” are in place, users with multimode devices will be able to maintain constant communication contact with almost anyone else on the planet. This level of technology will permit us to communicate at will with individuals and groups, without bounds.