The 57th Session of the International Statistical Institute, South Africa, August 15-22, 2009.

The 7th Annual Hawaii International Conference on Business, May 24-27, 2007.

2nd IEA International Research Conference, International Association for Evaluation of Educational Achievement (IEA), Washington, DC USA, November 9-11, 2006.

Measuring Well-Being and Societal Progress, JRC/OECD Workshop Series. Milan, Italy, June 19-21, 2006.

China – US Climate Change Forum, University of California, Berkeley, USA, May 23-24, 2006.

American Educational Research Association 2006 Annual Meeting: "Education Research in the Public Interest", San Fransisco, April 7-11, 2006.

7^th Hellenic - European Conference on Computer mathematics and its Applications, Athens, Greece, September 2005.

8th Annual Symi Symposium: "New Challenges to Democracy in the 21st Century". July 10-16, 2005, Rethymnon, Greece. (Organised by the Andreas Papandreou Foundation).

Towards a Transparency of Qualifications: A Service to All EU Citizens – The Point of View of All the Stakeholders in Education and Training. 2004 European Network of Educational Councils Conference. Brussels, October 25-27, 2004.

2003 Joint Statistical Meetings of the American Statistical Association, The Institute of Mathematical Statistics, the Canadian Statistical Society. San Francisco, August 2003.

2002 Joint Statistical Meetings of the American Statistical Association, The Institute of Mathematical Statistics, the Canadian Statistical Society. New York, August 2002.

5^th Hellenic - European Conference on Computer mathematics and its Applications, Athens, Greece, September 2001.

SESS-TIES 1999 International Conference “Environmetrics and Statistics in the Earth and Space Sciences” Athens, Greece, August 1999.

4^th Hellenic - European Conference on Computer mathematics and its Applications, Athens, Greece, September 1998.

13^th International Workshop on Statistical Modeling, New Orleans, USA, July 1998.

International Environmetrics Conference, Burlington, Ontario, Canada, August  1994.

American Statistical Association Winter Conference. Atlanda, Georgia, January 1994.

International Conference of the International Association for Statistical Education.Perugia, Italy, September 1993.

10. 49th Session of the International Statistical Institute. Firenze, Italy, September 1993.

American Statistical Association Winter Conference. Forte Lauderdale, Florida, January 1993.

20th European Meeting of Statisticians. Bath, England, September 1992.

Annual Conference of the Royal Statistical Society. Sheffield, England,September 1992.

Annual Meeting on Making Statistics More Effective in Business Schools. University of Tunnessee, Knoxville, Tennessee, June 1992.

48th Session of the International Statistical Institute. Cairo, Egypt, September 1991.

First International Symposium on Uncertainty Modeling and Analysis. Maryland, USA, December 1990.

2nd Bernoulli Society World Congress and 53rd IMS Annual Meeting.Uppsala, Sweden, August 1990.

XV-th International Biometric Conference, Budapest, Hungary. July 1990.

2nd National Meeting of the Greek Statistical Institute. Athens, Greece. February 1988.

First World Conference on Computational Statistics and Data Analysis. Shizuoka, Japan. September 1987.

46th Session of the International Statistical Institute. Tokyo, Japan. September 1987.

17th European Meeting of Statisticians. Thessaloniki, Greece. August 1987.

1st International Conference on Fibonacci numbers and their Applications. Patras, Greece. August 1984.

7th Balkan Congress of Mathematicians. Athens, Greece. December 1983.

1979 Meeting of the Institute of Mathematical Statistics. San Antonio, Texas, USA. March 1982.

177 Annual Meeting of the Institute of Mathemgtical Statistics. Vail, Colorade USA. August 1981.

1981 Joint Annual Meeting of the American Statistical Association and Biometric Society. Detroit, USA. August 1981.

Summer School and Research Conference in Statistical Distributions in Scientific Work. Trieste, Italy. August 1980.

Stochastic Modelling Conference. Trinity College, Dublin. May 1980.

42nd Session of the International Statistical Institute, Manila, Philippines. December 1979.

6th Conference in Probability Theory. Brasov, Romania. (Organised by the Centre of Mathematical Statistics of Bucharest and the Romanian Academy of Science). September 1979.

Colloquium on Analytic Method Functions in Probability Theory. Debrecen, Hungary. September 1977.

10th European Meeting of Statisticians, Leuven, Belgium. August 1977.