The topic of seismIcIty patterns is one in which significant advances in the
understanding of seismotectonics and earthquake hazard are being made, and in
which controversies have recently developed. This special issue grew out of a
workshop attended by forty-one participants on May 11/12, 1998 in Nikko, Japan.
The collection of papers we ultimately generated does not cover all aspects of
problems related to seismicity patterns, but a fair part of them. In a few cases, authors
wrote papers especially for this workshop, however, in general, they submitted papers
they fortuitously worked on at the time. Nevertheless, this collection of papers shows
what issues currently top the priority list in this field of research