PaCT-99 (Parallel Computing Technologies) was a four-day conference held in St. Petersburg on 6--10 September 1999. This represented the fifth international conference in PaCT series, which take place in Russia every odd year. The first, PaCT-91, was held in Novosibirsk (Academgorodok), 7--11 September, 1991. The second PaCT-93 was held in Obninsk (near Moscow), 30 August -- 4 September, 1993. The third, PaCT-95, was organized in St.Petersburg, 12--15 September, 1995 and the last fourth PaCT-97 was held in Yaroslavl 9-12 September, 1997.

PaCT-99 was jointly organized by the Institute of Computational Mathematics and Mathematical Geophysics of the Russian Academy of Sciences (Novosibirsk) and by the Electrotechnical University of St.Petersburg. The purpose of the conference was to bring together scientists working with theory, architecture, software, hardware and solution of large-scale problems in order to provide integrated discussions on Parallel Computing Technologies.

     The Conference attracted more than 100 participants from around the world. Authors from over 23 countries submitted 103 papers and there were 2 invited papers. Of those submitted, 47 papers were selected for the conference; in addition there were a number of posters presented. All the papers were internationally reviewed by at least three referees.

     As usual a demo session was organized for the participants. Three different tools were submitted (demonstration and tutorial) under the condition that the tools would be free for noncommercial use. One of them is WinALT (Russian Academy of Sciences, Novosibirsk), a software tool for fine-grain algorithm simulation. Another one is DEALed (State Technical University of St.-Petersburg), a tool for the development of real-time systems. The third is PLATINUM, a tool for workload construction on a workstation network run under UNIX.

     Many thanks to our sponsors: the Russian Academy of Sciences, the Russian Fund of Basic Research, the Russian State Committee for Higher Education, PARSYTEC (Germany) and the Institute of Computer Based Software Methodology and Technology (Japan) for their financial support. Organizers highly appreciate the help of the Association Antenne-Provence (France).