The Conference on Differential Equations and Their Applications (EQUADIFF 9) was held in Brno, August 25-29, 1997. It was organized by the Masaryk University, Brno in cooperation with Mathematical Institute of the Academy of Sciences, Technical University Brno, Union of Czech Mathematicians and Physicists, Union of Slovak Mathematicians and Physicists and other Czech scientific institutions with support of the International Mathematical Union. EQUADIFF 9 was attended by 268 participants from 32 countries and more than 50 accompanying persons and other guests.

This volume contains 20 papers by invited speakers in the conference. Together with this issue the following EQUADIFF 9 publications have been prepared:

- Proceedings of EQUADIFF 9 containing 12 survey papers mainly from the plenary lectures published by the Electronic Publishing House in both electronic and hard copy forms.

- CD ROM containing, in electronic form, a special EQUADIFF 9 issue of Archivum mathematicum, the Proceedings and 31 other papers submitted by the participants of the conference as well as other conference material (e.g. Abstracts, List of participants, and Program) - available to any participant of EQUADIFF 9.

This EQUADIFF 9 special issue of Archivum mathematicum is dedicated to Professor Frantisek Neuman, Chairman of the Conference, on the occasion of his sixtieth birthday. Professor Neuman obtained the Bolzano medal, an honor awarded to distinguished scientists by the Presidium of the Czech Academy of Sciences. Detailed information concerning the achievements of Professor Neuman as well as a list of his scientific publications can be found in the paper by O. Dosly ``Sixty years of Professor Frantisek Neuman", published in Mathematica Bohemica 123 (1998), No.1, 101-107 and in Czechoslovak Mathematical Journal 48 (1998), No.1, 177-183.

The printed version is identical to the electronic one on CD ROM in spite of slight changes in the usual Archivum mathematicum style. Our aim was to harness the possibilities of new computer technologies, and for this reason all EQUADIFF 9 publications on CD ROM were prepared in hypertext PDF form.

We would like to thank Professor Jaromir Kuben, who made this CD ROM a reality. We would also like to thank Professor Zuzana Dosla for her help during the preparation of this publication.

Brno, April 1998

Editors: R.P. Agarwal, J. Vosmansky