–– The last few years have seen the evolution of telecommunications from the classic architectures, mainly based on static and wired structures, to the new mobile solutions based on wireless technologies. This trend has led, on the one side, to the definition of the third–generation mobile telecommunication systems and, on the other, to the development of personal area networks. The standards that are supposed to play a leading role in these two fields in the near future are the Universal Mobile Telecommunication System (UMTS) and the Bluetooth (BT) radio technology, respectively. In this paper, we advocate that a hybrid architecture of UMTS and Bluetooth can take advantage of the complementary characteristics of these two technologies and provide a total solution for an indoor communication environment. We envision a cooperating scenario in which small Bluetooth networks (scatternets) offer basic wireless connectivity to several peripheral units scattered over small areas, while...