It is probably true quite generally that in the history of human
thinking the most fruitful developments frequently take place at those
points where two different lines of thought meet. Hence, if they
actually meet, that is, if they are at least so much related to each
other that a real interaction can take place, then one may hope that new
and interesting developments may follow. Werner Heisenberg This volume
contains papers presented at the August 1992 NATO Advanced Study
Institute on Wavelets and Their Applications. The conference was held at
the beautiful Il Ciocco resort near Lucca, in the glorious Tuscany
region of northern Italy. Once again we gathered at this idyllic spot to
explore and extend the reciprocity between mathematics and engineering.
The dynamic interaction between world-renowned scientists from the usu-
ally disparate communities of pure mathematicians and applied
scientists, which occurred at our 1989 and 1991 ASI's, continued at this
meeting. Wavelet theory and technology is in an important growth stage
at which theoretical and practical results are being compared with
existing methods. There have been spectacular wavelet successes and
sobering comparisons with traditional ideas-but still there is a wide
expanse of scientific problems to explore. Since these problems lie at
the forefront of both pure mathematics and applied science, our NATO ASI
was especially pertinent at this time.