Art & Mathematics, Venice, Italy, 2002
Art & Mathematics, Cooper Union, New York, New York 2000
Mathematics and Culture, Bologna, Italy 2000
Colloque Mathematiques et Arts, Maubeuge, France 2000
Wenner-Gren Foundation, Stockholm, Sweden 2000
University of California, Berkeley, CA 1998
Southwestern College, Winfield, Kansas 1998
University of the Basque Country, San Sebastian, Spain 1998
Smithsonian Institution, Washington, DC 1996
The Century Association, New York City, NY 1995
American Association for the Advancement of Science, San Francisco 1994
SUNY, Albany, NY 1993
Yale University, New Haven, CT 1993
Silvermine Guild, New Canaan, 1993
SUNY, Albany, NY 1992
Lecture tour, (six cities) Australia, 1992
Scripps College, Claremont, CA 1991
Cummer Gallery of Art, Jacksonville, FL 1990
State University of New York, Stonybrook, NY 1989
New Canaan Library, New Canaan, CT1989
Rhode Island College, RI, 1988
Yale University, New Haven, CT (architectural jury) 1986
Silvermine Guild for Arts, New Canaan, 1986
Katonah Gallery, Katonah, N.Y., 1985
Westport Center of Arts,Westport, CT, 1985
Darien Library, Darien, CT, 1984
Stamford Library, Stamford, CT, 1983
The New School, New York City, NY, 1982
Boston Visual Artists Union, Boston, MA, 1981
Columbia University, New York City, NY, 1981
Hunter College, New York City, NY, 1981
Yale University, New Haven, CT (architectural jury) 1981