Wireless mobile access to the Internet will add a new dimension to the way we access information and communicate. This volume is devoted to the presentation of research on the deployment of the network protocols and services for mobile hosts and wireless communication on the Internet. A lot of wireless technologies have already appeared, including IEEE 802.11b, Bluetooth, HiperLAN/2, GPRS and UTMS. All of them have the same goal: offering wireless connectivity with minimum service disruption between mobile handovers. The mobile world is divided into two parts: firstly, mobile nodes can be attached to several access points when mobiles move around; secondly ad-hoc networks exist which do not use any infrastructure to communicate. With this model all nodes are mobiles and they co-operate to forward information between each other. This text presents these two methods of Internet access and contains research papers that propose extensions and optimizations to the existing protocols for mobility support.