Intelligence in Networks is a concept, the meaning of which is highly related to the time-period when it is used. In the 1960s, 1970s and 1980s, it was mainly related to the teleservice repertoire `an sich'. In the 1990s, it is more related to efficient flexibility in the introduction of new teleservices and teleservice repertoire. This state-of-the-art text sets out to identify and study issues related to solutions for increasing intelligence in networks. As examples, intelligence networks (IN), telecommunication information networking architecture (TINA) and mobile agents and active networks are different solutions for improving the grade of network intelligence. The areas under discussion include research and development within various closely related fields such as: Teleservices, service architecture and service creation; Middleware and specification languages; Mobile agents, active networks, plug-and-play issues; and Quality of service and performance.£/LIST£ Intelligence in Networks contains the proceedings of SMARTNET'99, the fifth in a series of conferences on intelligence in networks sponsored by the International Federation for Information Processing (IFIP), at the Asian Institute of Technology, Pathumthani, Thailand in November 1999.