Mobile communications bring major changes in our daily lives. The launch system of 3rd generation mobile in 2001 in Japan and since 2002 for the rest of the world, will enable us to communicate anytime and anywhere, using a variety of services that have until now only available to users of fixed networks. At the end of 2003, there is expected to more than one billion mobile phones worldwide, which exceeds the number of fixed telephone lines is projected for that date. Describing the current situation and future development of UMTS (Universal Mobile Telecommunications System) Outlining the reasons and motives behind the evolution of new mobile phone system Analyze requirements and describes the UMTS radio system UTRA (UMTS Terrestrial Radio Access) and UTRAN (UTRA Network) together with the Network Core Issues Provide an overview of new voice, data and multimedia services that will be available to users Review of current trends that will affect future research and discuss key topics, including SDMA (Space Division Multiple Access) smart antennas and software radio Written in a style accessible, UMTS: Mobile Communications for the Future will prove indispensable reading for all those working in the field of mobile communciations.