European Committee:

Member of the Information and Communication Panel of the Scientific Councel of the European Research Councel (ERC)

Prize Committee:

Goedel Prize Committee 2005-2008.

Editorial board member:

SN Computer Science, Springer.
Distributed Computing, Springer, 1987-2003.
Information Processing Letters, North-Holland/Elsevier
Theory of Computing Systems (TOCS formerly Mathematical Systems Theory), Springer Verlag
`Parallel Processing Letters', World Scientific Publishers, Singapore,
Entropy (ISSN 1099-4300; CODEN: ENTRFG), An International and Interdisciplinary Peer-Reviewed Journal of Entropy and Information Studies.Published online quarterly.
`International Journal of Foundations of Computer Science (IJFCS)', World Scientific Publishers, Singapore,
Guest editor `Journal of Computer and System Sciences', special issue on selected papers from EuroCOLT'95.
`Journal of New Generation Computer Systems', (Akademie-Verlag, Berlin)
`Frontiers in Computing Systems Research', Plenum Annual Review Book Series, Plenum Press.
Member of the Scientific Board, `Encyclopaedia of Mathematics', Reidel (updated and annotated translation of the Soviet `Mathematical Encyclopaedia'.)

Steering Committee:

Vice Chairman Steering Committee of the Annual Conference on Distributed Computing (DISC) 2004-2006.
Member Steering Committee of the Annual Workshop on Distributed Algorithms on Graphs (WDAG) 1990-1996.
Member Steering Committee of the Annual European Conference on Computational Learning Theory (EuroCOLT) 1992-1996.

Selected Program Committees:

Program Committee member 7th Conference on Reversible Computation July 16th-17th, 2015, Grenoble, France.
Program Committee member Tenth International Conference on Computability, Complexity and Randomness (CCR 2015) 22-26 June 2015, Heidelberg, Germany
Program Committee member 2013 ACM International Conference on Computing Frontier (CF 2013), Ischia, Italy, May 14-16, 2013.
Program Committee member 7th Conference on Computability, Complexity and Randomness (CCR 2012), 2-6 July 2012, Isaac Newton Institute (INI), Cambridge, UK.
Technical Program Committee member 2012 IEEE International Symposium on Information Theory - ISIT 2012, MIT, Cambridge, Mass., July 1--??, 2012.
Program Committee member Melbourne, Australia Wedn 30/Nov/2011 - Fri 2/Dec/2011
Program Committee member, 1st International Conference on Data Compression, Communication, and Processing (CCP2011) Palinuro (Cilento Coast) - Salerno, Italy, June 21-24, 2011
Program Committee member, 13th International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS 2011) Shinagawa (Tokyo), Japan 4-7 October 2011.
Program Committee member, 7th International Conference on Natural Computation (ICNC11), July 26-28, 2011 in Shanghai, China.
Program Committee member, ICEC 2010, International Conference on Evolutionary Computing, 14--26 Oct., 2010, Valencia, Spain.
Program Committee member, ADMA10, the Sixth International Conference on Advanced Data Mining and Applications, Chongqing, China, November 19-20, 2010, adma2010@cqu.edu.cn .
Program Committee for the 2nd Workshop on Reversible Computation, Bremen, Germany, July 2--3, 2010. http://www.informatik.uni-bremen.de/rc/cms/
Program Committee for BENELEARN 2010, Leuven, Belgium, May, 2010.
6th International Conference on Natural Computation (ICNC'10), 10-12 August 2010, Yantai, China http://icnc-fskd2010.ytu.edu.cn/
Program Committee 2nd SIBIRCON, Irkutsk, Russia, July 2010, organized by IEEE Region 8 and IEEE Russia Siberia Section.
Program Committee member, STACS 2010, March 4--6, Nancy, France.
Program Committee member, ADMA09, the Fifth International Conference on Advanced Data Mining and Applications, Beijing, China, 17-19 August 2009, adma2009@bnu.edu.cn .
Program Committee for Reversible Computation Workshop, 22 March 2009, York, UK.
Program Committee for BENELEARN 2008, Liege, Belgium, May, 2008.
Program Committee 1st SIBIRCON, Novosibirsk, Russia, from July 21 to July 25, 2008 organized by IEEE Region 8 and IEEE Russia Siberia Section.
Vice-Chair, Conference on Information Theory and Statistical Learning (ITSL), Harnessing information processing in biological systems, International conference in conjunction with WORLDCOMP'08 Las Vegas, Nevada (June 23-24, 2008)
Program Committee 33rd International Symposium on Mathematical Foundations of Computer Science, held August 25 - 29, 2008, in Torun (Thorn in German) in Poland.
Program Committee for BENELEARN 2007, Amsterdam, 14-15 May, 2007.
Program Committee member, ADMA07, the Third International Conference on Advanced Data Mining and Applications, Harbin, China, August 6-8, 2007, http://db.cs.ualberta.ca/adma07/
Program Committee member, ADMA06, the Second International Conference on Advanced Data Mining and Applications: http://www.itee.uq.edu.au/~adma06/ 14-16 August in Xi'an, China.
Program committee member, 26th IEEE International Conference on Distributed Computing Systems (ICDCS-26), Lisboa, Portugal July 4-7, 2006. http://icdcs2006.di.fc.ul.pt
TPC membership for the Conference on Applied Practice and Theory on Computation and Control, APTCC 2005. http://www.iaria.org/conferences/APTCC05.html The International Conference on Applied Practice and Theory on Computation and Control Tahiti, French Polynesia October 23-28, 2005
ADMA 2005 (Advanced Data Mining and Applications), Wuhan, China.
The First Int'l. Workshop on Reversible Computing A Key Challenge for 21st Century Computing; a special session at ACM Computing Frontiers 2005 (CF'05) Ischia, Italy, May 4-6, 2005
16th European Conference on Machine Learning (ECML) and the 9th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD). in Porto, Portugal 2-7 Oct. '05.
15th European Conference on Machine Learning (ECML) and the 10th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD), October 1004, in Pisa, Italy.
DISC 2004: The 18th Annual Conference on Distributed Computing, October 4-7, Amsterdam, The Netherlands.
29th International Symposium on Mathematical Foundations of Computer Science (MFCS-2004), 2004, Prague, Czech Republic.
14th European Conference on Machine Learning (ECML-2003), Dubrovnik, Croatia, September 22-26 2003.
14th Annual International Symposium on Algorithms and Computation (ISAAC'03), Kyoto, December 15-17, 2003.
13th European Conference on Machine Learning (ECML'02), co-located in Helsinki with the 6th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD'02)
Eighth Annual International Computing and Combinatorics Conference (COCOON'02), Singapore, August 2002.
International Conference on Algorithms, Languages, and Programming, (ICALP), Malaga (Spain), 2002.
12th European Conference on Machine Learning (ECML '01), 2001 co-located with the 5th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD'01)
Ninth International Conference on Intelligent Systems: Artificial Intelligence Applications for the New Millennium, June 14-17, 2000 The Galt House Hotel Louisville, KY USA
IFIP International Conference on Theoretical Computer Science (IFIP TCS2000) --- Exploring New Frontiers of Theoretical Informatics --- August 17 - 19, 2000 Tohoku University, Sendai, Japan
Organizing/Program Committee "Workshop on Complexity and Inference" for the "Computational Information Theory and Coding Year" (2001-2002) at DIMACS at Rutgers University.
GECCO-99, Genetic and Evolutionary Computation Conference | July 14-17, 1999, Orlando, Florida USA, a joint meeting of the | Eighth International Conference on Genetic Algorithms (ICGA-99) and the Fourth Annual Genetic Programming Conference (GP-99).
ICML-99, the 16th International Machine Learning conference, Slowakia, 1999.
6th bi-annual Workshop on Algorithms and Data Structures, WADS'99, Vancouver, Canada, 1999.
6th International Colloquium on Structural Information and Communication Complexity (SIROCCO'99), 1999.
Netherlands Artificial Intelligence Conference, 1998.
23th International Symposium on Mathematical Foundations of Computer Science(MFCS-1998), 1998, Brno, Slowac Republic
ACM Conference on Principles of Distributed Computing (PODC 98), Puerto Vallarta, Mexico.
European Symposium on Algorithms ESA'98, Venice, Italy, August 1998.
The Fifth International Symposium on Artificial Intelligence and Mathematics 4-6 January 1998, Ft. Lauderdale, Florida
11th International Workshop on Distributed Algorithms, WDAG-11, Saarbruecken, Germany, 1997.
Compression and Complexity of SEQUENCES 1997, In cooperation with the IEEE Data Compression Conference Positano (Amalfitan Coast) - Salerno, Italy June 11-13 1997
School on Natural Computation (SNAC), 25-29.8.1997, Turku, Finland.
Algorithmic Learning Theory Conference (ALT-1997), Sendai, Japan, 1997.
5th bi-annual Workshop on Algorithms and Data Structures, WADS'97, Halifax, Canada, in August 1997.
10th European Conference on Machine Learning (ECML-1997), Prague, Czech Republic, 1997.
Fourth International Conference on "Logical Foundations of Computer Science" (LFCS'97) on July 6-12, 1997, in Yaroslavl, Russia.
Third Annual International Computing and Combinatorics Conference (COCOON'97), Shanghai, China, August 1997.
Conference on Information, Statistics and Induction in Science (ISIS), Melbourne, Australia, 20 - 23 August, 1996.
PHYSCOMP96 (IEEE Physics and Computation Conference), Boston, Mass., 1996.
International Conference on Algorithms, Languages, and Programming, Paderborn (ICALP), Germany, 1996.
Fundamentals of Computation Theory (FCT), August 1995, Dresden, Germany.
Program Committee Chair, 2nd EURO-COLT, Conference on Computational Learning Theory Barcelona, Spain, 1995.
PHYSCOMP94 (IEEE Physics and Computation Conference), Dallas, Texas, 1994.
Program Committee Co-Chair, 8th International Workshop on Distributed Algorithms, WDAG-8, Amsterdam, Netherlands, 1994.
Conpar94 - VAPP VI (Concurrent and Parallel Computation 94 and Vector and Parallel Processors in Computer Science VI), Linz, Germany, September 6-8 1994.
7th European Conference on Machine Learning, Sicily, 1994.
Local Arrangments Co-Chair, 9th Annual IEEE Structure in Complexity Theory Conference (the series is now renamed ``Complexity Theory Conference''), Amsterdam, 1994.
EURO-COLT '93, Conference on Computational Learning Theory London, 1993.
Workshop on Biases in Inductive Learning, Aberdeen, Scotland, 1992.
Computer Science in the Netherlands '92.
Conpar92 - VAPP V (Concurrent and Parallel Computation 92 and Vector and Parallel Processors in Computer Science V), Lyon, France, 92.
Program Subcommittee Chair, Theory of Computation, CompEuro 92, the IEEE International Conference on Computer Systems and Software Engineering
STACS, Paris, France, 1991.
5th International Workshop on Distributed Algorithms, WDAG-5, Delphi, Greece, 1991.
Chartered to form and chair IFIP Special Working Group WG 14.5 on Machine Learning, 1991 -
Program Committee, 6th Annual IEEE Structure in Complexity Theory Conference, Chicago, Illinois, 1991.
IFIP Special Working Group WG 14.2 on Descriptional Complexity, 1990 -
Steering Committee, International Workshop on Distributed Algorithms (WDAG), 1990 -
Closing Panel, Symposium on Application of Minimal Length Encoding, AAAI90 Spring Symposium Series, Stanford University, Stanford, California, 27-29 March, 1990.
4th International Workshop on Distributed Algorithms, WDAG-4, Bari, Italy, 1990.
Publiciteits commissie van het Wiskundig Genootschap (Publicity Committee Dutch Mathematical Society), 1989 -
3rd International Workshop on Distributed Algorithms, WDAG-3, Nice, France, 1989.
4th Annual IEEE Structure in Complexity Theory Conference, Eugene, Oregon, 1989.
Committee of the Society for Theoretical Computer Science in the Netherlands (Werkgemeenschap Theoretische Informatica), member.
1987 Princeton University - AT\&T Bell Labs (Holmdel, N.J.) Workshop on Formal Models of General Purpose Distributed Computation
Aegean Workshop on Computing: VLSI Algorithms and Architectures, 2nd International Workshop on Parallel Computing and VLSI, Attica, Greece, July 8-11, 1986.

Membership in International organizations:

EU PASCAL network of excellence PASCAL - Pattern Analysis, Statistical Modelling and Computational Learning
EU project RESQ (Resources for Quantum Computing), funded by the European Union under contract IST-2001-37559.
European Community ESPRIT Working Group in Neural and Computational Learning Theory (NeuroCOLT2)
European Science Foundation Programme on Quantum Information Processing.
European Union ``Quantum Algorithms and Information Processing'' (QAIP) Project IST-1999-11234 Fifth Framework Program.
RoboCup
International Federation for Information Processing (IFIP) WG 1.2 Description Complexity
International Federation for Information Processing (IFIP) WG 1.4 Computational Learning Theory (Co-chair)

Organization:

Organizer: 29.01.-03.02.06, Dagstuhl Seminar Nº 06051 Kolmogorov Complexity and Applications Dagstuhl, Wadern, Germany (with Wolfgang Merkle and Marcus Hutter).
Organization Co-chair: The 18th Annual Conference on Distributed Computing (DISC 2004). (With Jaap-Henk Hoepman). The 18th Annual Conference on Distributed Computing (DISC 2004), held from Monday, October 4, through Friday, October 7, 2004, Amsterdam, The Netherlands .
Organizer: Centennial Seminar on Kolmogorov Complexity and Applications, 27.04.-02.05.2003, Seminar Nº 03181, SCHLOSS DAGSTUHL,(with B. Durand (Marseille, F), L.A. Levin (Boston Univ., USA), W. Merkle (Heidelberg, D), A. Shen (IITP - Moscow, RUS).
Organization Co-chair: COLT 2001: The Fourteenth Annual Conference on Computational Learning Theory and EUROCOLT 2001: The Fifth European Conference on Computational Learning Theory. (With Peter Gruenwald).
Organization Chair: 9th Annual IEEE Structure in Complexity Theory Conference, Amsterdam, 1994.
Organization Co-Chair: Distributed Algorithms: 8th International Workshop, WDAG 1994 (the series now named DISC), Terschelling, the Netherlands, September 29 - October 1, 1994. (With Gerard Tel).

Membership in Dutch organizations: