Book excerpt: It is becoming quite clear that there will be important technological advances in - bile and wireless connectivity, known as third-/fourth-generation (3G and 4G) mobile telecommunications systems. As a result we will be surrounded by ever-growing m- tidomain (technical and administrative) heterogeneous communications in both wired and wireless networks. This resulting environment deals with communication in m- tizoned networks, where people, devices, appliances and servers are connected to each other via different kinds of networks. Networks will be pervasive, ubiquitous, multis- vice, multioperatorand multiaccess. The mobility trend will also be spurred forward by the growing availability of mobile-enabled handheld devices. Mobile systems are expected to provide mobile users with cost-effective, secure, yet ubiquitous service access anywhere and anytime. Users will then continue to enjoy the new-found freedom mobile access provides and will have increasingly high exp- tations of mobility-aware applications that should be capable of seamlessly supporting the mobile lifestyle. The papers in this volume discuss issues from models, platforms, and architectures for mobility-aware systems to security, mobile agent technologies, sensitive com- nications, context awareness, mobile applications and management. They cover both practical experience and novel research ideas and concepts.